Magnetometer - Knowledge (XXG)

1196:. An alternating current is applied to the drive winding, which drives the core in a continuous repeating cycle of saturation and unsaturation. To an external field, the core is alternately weakly permeable and highly permeable. The core is often a toroidally wrapped ring or a pair of linear elements whose drive windings are each wound in opposing directions. Such closed flux paths minimise coupling between the drive and sense windings. In the presence of an external magnetic field, with the core in a highly permeable state, such a field is locally attracted or gated (hence the name fluxgate) through the sense winding. When the core is weakly permeable, the external field is less attracted. This continuous gating of the external field in and out of the sense winding induces a signal in the sense winding, whose principal frequency is twice that of the drive frequency, and whose strength and phase orientation vary directly with the external-field magnitude and polarity. 1165:; i.e., magnetised, unmagnetised, inversely magnetised, unmagnetised, magnetised, and so forth. This constantly changing field induces a voltage in the second coil which is measured by a detector. In a magnetically neutral background, the input and output signals match. However, when the core is exposed to a background field, it is more easily saturated in alignment with that field and less easily saturated in opposition to it. Hence the alternating magnetic field and the induced output voltage, are out of step with the input current. The extent to which this is the case depends on the strength of the background magnetic field. Often, the signal in the output coil is integrated, yielding an output analog voltage proportional to the magnetic field. 661:

against a spring. Commonly a capacitive load cell or cantilever is used because of its sensitivity, size, and lack of mechanical parts. Faraday force magnetometry is approximately one order of magnitude less sensitive than a SQUID. The biggest drawback to Faraday force magnetometry is that it requires some means of not only producing a magnetic field, but also producing a magnetic field gradient. While this can be accomplished by using a set of special pole faces, a much better result can be achieved by using set of gradient coils. A major advantage to Faraday force magnetometry is that it is small and reasonably tolerant to noise, and thus can be implemented in a wide range of environments, including a

432: 602:(VSMs) detect the dipole moment of a sample by mechanically vibrating the sample inside of an inductive pickup coil or inside of a SQUID coil. Induced current or changing flux in the coil is measured. The vibration is typically created by a motor or a piezoelectric actuator. Typically the VSM technique is about an order of magnitude less sensitive than SQUID magnetometry. VSMs can be combined with SQUIDs to create a system that is more sensitive than either one alone. Heat due to the sample vibration can limit the base temperature of a VSM, typically to 2 kelvin. VSM is also impractical for measuring a fragile sample that is sensitive to rapid acceleration. 1520: 1221:, or superconducting quantum interference devices, measure extremely small changes in magnetic fields. They are very sensitive vector magnetometers, with noise levels as low as 3 fT Hz in commercial instruments and 0.4 fT Hz in experimental devices. Many liquid-helium-cooled commercial SQUIDs achieve a flat noise spectrum from near DC (less than 1 Hz) to tens of kilohertz, making such devices ideal for time-domain biomagnetic signal measurements. SERF atomic magnetometers demonstrated in laboratories so far reach competitive noise floor but in relatively small frequency ranges. 951:. When a caesium atom within the chamber encounters a photon from the laser, it is excited to a higher energy state, emits a photon and falls to an indeterminate lower energy state. The caesium atom is "sensitive" to the photons from the laser in three of its nine energy states, and therefore, assuming a closed system, all the atoms eventually fall into a state in which all the photons from the laser pass through unhindered and are measured by the photon detector. The caesium vapour has become transparent. This process happens continuously to maintain as many of the electrons as possible in that state. 1120: 1738:

spacing at 100 m elevation, with readings every 10 meters or more. To overcome the asymmetry in the data density, data is interpolated between lines (usually 5 times) and data along the line is then averaged. Such data is gridded to an 80 m × 80 m pixel size and image processed using a program like ERMapper. At an exploration lease scale, the survey may be followed by a more detailed helimag or crop duster style fixed wing at 50 m line spacing and 50 m elevation (terrain permitting). Such an image is gridded on a 10 x 10 m pixel, offering 64 times the resolution.

1904: 591:

changing dc field), as occurs in capacitor-driven pulsed magnets. These measurements require differentiating between the magnetic field produced by the sample and that from the external applied field. Often a special arrangement of cancellation coils is used. For example, half of the pickup coil is wound in one direction, and the other half in the other direction, and the sample is placed in only one half. The external uniform magnetic field is detected by both halves of the coil, and since they are counter-wound, the external magnetic field produces no net signal.

1792: 1431:, coal mine hazards, unexploded ordnance, toxic waste drums, as well as a wide range of mineral deposits and geological structures. They also have applications in heart beat monitors, concealed weapons detection, military weapon systems positioning, sensors in anti-locking brakes, weather prediction (via solar cycles), steel pylons, drill guidance systems, archaeology, plate tectonics, radio wave propagation, and planetary exploration. Laboratory magnetometers determine the magnetic dipole moment of a magnetic sample, typically as a function of 681:. Faraday rotation magnetometry utilizes nonlinear magneto-optical rotation to measure a sample's magnetization. In this method a Faraday modulating thin film is applied to the sample to be measured and a series of images are taken with a camera that senses the polarization of the reflected light. To reduce noise, multiple pictures are then averaged together. One advantage to this method is that it allows mapping of the magnetic characteristics over the surface of a sample. This can be especially useful when studying such things as the 1112: 443:, consisting of a magnetized needle whose orientation changes in response to the ambient magnetic field, is a simple type of magnetometer, one that measures the direction of the field. The oscillation frequency of a magnetized needle is proportional to the square-root of the strength of the ambient magnetic field; so, for example, the oscillation frequency of the needle of a horizontally situated compass is proportional to the square-root of the horizontal intensity of the ambient field. 1097:, nickel-iron alloy, whose electrical resistance varies with a change in magnetic field. They have a well-defined axis of sensitivity, can be produced in 3-D versions and can be mass-produced as an integrated circuit. They have a response time of less than 1 microsecond and can be sampled in moving vehicles up to 1,000 times/second. They can be used in compasses that read within 1°, for which the underlying sensor must reliably resolve 0.1°. 33: 1362: 424: 1279:. For the case of alkali, the coherence times were greatly limited due to spin-exchange relaxation. A major breakthrough happened at the beginning of the 2000 decade, Romalis group in Princeton demonstrated that in such a low field regime, alkali coherence times can be greatly enhanced if a high enough density can be reached by high temperature heating, this is the so-called 185: 1415: 665:. Faraday force magnetometry can also be complicated by the presence of torque (see previous technique). This can be circumvented by varying the gradient field independently of the applied DC field so the torque and the Faraday force contribution can be separated, and/or by designing a Faraday force magnetometer that prevents the sample from being rotated. 1814:. The iPhone 3GS has a magnetometer, a magnetoresistive permalloy sensor, the AN-203 produced by Honeywell. In 2009, the price of three-axis magnetometers dipped below US$ 1 per device and dropped rapidly. The use of a three-axis device means that it is not sensitive to the way it is held in orientation or elevation. Hall effect devices are also popular. 1511:

stress-magnetisation relationship. However the effect of mechanical stress on measured magnetic field near the specimen is claimed to be proven in many scientific publications. There have been efforts to solve the inverse problem of magnetisation-stress resolution in order to quantify the stress based on measured magnetic field.

118:) metals, but can detect such metals at a much greater distance than conventional metal detectors, which rely on conductivity. Magnetometers are capable of detecting large objects, such as cars, at over 10 metres (33 ft), while a conventional metal detector's range is rarely more than 2 metres (6 ft 7 in). 1703: 1671:, and magnetically-triggered mines. However, submarines are never completely de-magnetised. It is possible to tell the depth at which a submarine has been by measuring its magnetic field, which is distorted as the pressure distorts the hull and hence the field. Heating can also change the magnetization of steel. 2045:

Recording data and image processing is superior to real-time work because subtle anomalies often missed by the operator (especially in magnetically noisy areas) can be correlated between lines, shapes and clusters better defined. A range of sophisticated enhancement techniques can also be used. There

1674:

Submarines tow long sonar arrays to detect ships, and can even recognise different propeller noises. The sonar arrays need to be accurately positioned so they can triangulate direction to targets (e.g. ships). The arrays do not tow in a straight line, so fluxgate magnetometers are used to orient each

1334:

The calibration of magnetometers is usually performed by means of coils which are supplied by an electrical current to create a magnetic field. It allows to characterize the sensitivity of the magnetometer (in terms of V/T). In many applications the homogeneity of the calibration coil is an important

958:

In the most common type of caesium magnetometer, a very small AC magnetic field is applied to the cell. Since the difference in the energy levels of the electrons is determined by the external magnetic field, there is a frequency at which this small AC field makes the electrons change states. In this

885:

using a solenoid, a low power radio-frequency field is used to align (polarise) the electron spin of the free radicals, which then couples to the protons via the Overhauser effect. This has two main advantages: driving the RF field takes a fraction of the energy (allowing lighter-weight batteries for

660:

Faraday force magnetometry uses the fact that a spatial magnetic field gradient produces force that acts on a magnetized object, F = (M⋅∇)B. In Faraday force magnetometry the force on the sample can be measured by a scale (hanging the sample from a sensitive balance), or by detecting the displacement

1782:

Because hills and valleys under the aircraft make the magnetic readings rise and fall, a radar altimeter keeps track of the transducer's deviation from the nominal altitude above ground. There may also be a camera that takes photos of the ground. The location of the measurement is determined by also

1286:

The main interest of optically-pumped magnetometers is to replace SQUID magnetometers in applications where cryogenic cooling is a drawback. This is notably the case of medical imaging where such cooling imposes a thick thermal insulation, strongly affecting the amplitude of the recorded biomagnetic

685:

on superconductors. Microfabricated optically pumped magnetometers (μOPMs) can be used to detect the origin of brain seizures more precisely and generate less heat than currently available superconducting quantum interference devices, better known as SQUIDs. The device works by using polarized light

619:

Magnetic torque magnetometry can be even more sensitive than SQUID magnetometry. However, magnetic torque magnetometry doesn't measure magnetism directly as all the previously mentioned methods do. Magnetic torque magnetometry instead measures the torque τ acting on a sample's magnetic moment μ as a

1836:

methods are preferred to magnetometers as the primary survey method for oil exploration although magnetic methods can give additional information about the underlying geology and in some environments evidence of leakage from traps. Magnetometers are also used in oil exploration to show locations of

1737:

Developed countries such as Australia, Canada and USA invest heavily in systematic airborne magnetic surveys of their respective continents and surrounding oceans, to assist with map geology and in the discovery of mineral deposits. Such aeromag surveys are typically undertaken with 400 m line

1325:

Large volume detectors have achieved a sensitivity of 200 aT Hz. This technology has greater sensitivity per unit volume than SQUID detectors. The technology can also produce very small magnetometers that may in the future replace coils for detecting radio-frequency magnetic fields. This technology

962:

Another type of caesium magnetometer modulates the light applied to the cell. This is referred to as a Bell-Bloom magnetometer, after the two scientists who first investigated the effect. If the light is turned on and off at the frequency corresponding to the Earth's field, there is a change in the

954:

At this point, the sample (or population) is said to have been optically pumped and ready for measurement to take place. When an external field is applied it disrupts this state and causes atoms to move to different states which makes the vapour less transparent. The photo detector can measure this

162:

of units. 10,000 gauss are equal to one tesla. Measurements of the Earth's magnetic field are often quoted in units of nanotesla (nT), also called a gamma. The Earth's magnetic field can vary from 20,000 to 80,000 nT depending on location, fluctuations in the Earth's magnetic field are on the order

1203:

Phase synchronous detection is used to extract these harmonic signals from the sense winding and convert them into a DC voltage proportional to the external magnetic field. Active current feedback may also be employed, such that the sense winding is driven to counteract the external field. In such

1563:

popularised 'geophys', including magnetic techniques used in archaeological work to detect fire hearths, walls of baked bricks and magnetic stones such as basalt and granite. Walking tracks and roadways can sometimes be mapped with differential compaction in magnetic soils or with disturbances in

1176:

measure the direction and magnitude of magnetic fields. Fluxgates are affordable, rugged and compact with miniaturization recently advancing to the point of complete sensor solutions in the form of IC chips, including examples from both academia and industry. This, plus their typically low power

515:

of a sample material. Unlike survey magnetometers, laboratory magnetometers require the sample to be placed inside the magnetometer, and often the temperature, magnetic field, and other parameters of the sample can be controlled. A sample's magnetization, is primarily dependent on the ordering of

106:

reference. Magnetometers are also used by the military as a triggering mechanism in magnetic mines to detect submarines. Consequently, some countries, such as the United States, Canada and Australia, classify the more sensitive magnetometers as military technology, and control their distribution.

1965:

are pairs of magnetometers with their sensors separated, usually horizontally, by a fixed distance. The readings are subtracted to measure the difference between the sensed magnetic fields, which gives the field gradients caused by magnetic anomalies. This is one way of compensating both for the

1024:

Vector magnetometers measure one or more components of the magnetic field electronically. Using three orthogonal magnetometers, both azimuth and dip (inclination) can be measured. By taking the square root of the sum of the squares of the components the total magnetic field strength (also called

2013:

Some total field sensors give different readings depending on their orientation. Magnetic materials in the sensor itself are the primary cause of this error. In some magnetometers, such as the vapor magnetometers (caesium, potassium, etc.), there are sources of heading error in the physics that

1778:

Airborne Magnetometers detect the change in the Earth's magnetic field using sensors attached to the aircraft in the form of a "stinger" or by towing a magnetometer on the end of a cable. The magnetometer on a cable is often referred to as a "bomb" because of its shape. Others call it a "bird".

1008:

The caesium and potassium magnetometers are typically used where a higher performance magnetometer than the proton magnetometer is needed. In archaeology and geophysics, where the sensor sweeps through an area and many accurate magnetic field measurements are often needed, caesium and potassium

590:

Inductive pickup coils (also referred as inductive sensor) measure the magnetic dipole moment of a material by detecting the current induced in a coil due to the changing magnetic moment of the sample. The sample's magnetization can be changed by applying a small ac magnetic field (or a rapidly

575:

SQUIDs are a type of magnetometer used both as survey and as laboratory magnetometers. SQUID magnetometry is an extremely sensitive absolute magnetometry technique. However SQUIDs are noise sensitive, making them impractical as laboratory magnetometers in high DC magnetic fields, and in pulsed

1615:

The best survey results are achieved on the ground in high-resolution surveys (with approximately 10 m line spacing and 0.5 m station spacing). Bore-hole magnetometers using a Ferretcan also assist when coal seams are deep, by using multiple sills or looking beneath surface basalt flows.

1510:

Magnetometers are used to measure or monitor mechanical stress in ferromagnetic materials. Mechanical stress will improve alignment of magnetic domains in microscopic scale that will raise the magnetic field measured close to the material by magnetometers. There are different hypothesis about

610:

Pulsed-field extraction magnetometry is another method making use of pickup coils to measure magnetization. Unlike VSMs where the sample is physically vibrated, in pulsed-field extraction magnetometry, the sample is secured and the external magnetic field is changed rapidly, for example in a

2025:

hats are very popular in Australia, but their steel rims must be removed before use on magnetic surveys. Steel rings on notepads, steel capped boots and steel springs in overall eyelets can all cause unnecessary noise in surveys. Pens, mobile phones and stainless steel implants can also be

1757:

There are many challenges interpreting magnetic data for mineral exploration. Multiple targets mix together like multiple heat sources and, unlike light, there is no magnetic telescope to focus fields. The combination of multiple sources is measured at the surface. The geometry, depth, or

1966:

variability in time of the Earth's magnetic field and for other sources of electromagnetic interference, thus allowing for more sensitive detection of anomalies. Because nearly equal values are being subtracted, the noise performance requirements for the magnetometers is more extreme.

1553:

are popular due to their compact configuration and relatively low cost. Gradiometers enhance shallow features and negate the need for a base station. Caesium and Overhauser magnetometers are also very effective when used as gradiometers or as single-sensor systems with base stations.

1243:) to operate, hence the packaging requirements to use them are rather stringent both from a thermal-mechanical as well as magnetic standpoint. SQUID magnetometers are most commonly used to measure the magnetic fields produced by laboratory samples, also for brain or heart activity ( 560:

between different types of magnetic orders that occur at critical temperatures or magnetic fields. This type of magnetometry measurement is very important to understand the magnetic properties of materials in physics, chemistry, geophysics and geology, as well as sometimes biology.

959:

new state, the electrons once again can absorb a photon of light. This causes a signal on a photo detector that measures the light passing through the cell. The associated electronics use this fact to create a signal exactly at the frequency that corresponds to the external field.

620:

result of a uniform magnetic field B, τ = μ × B. A torque is thus a measure of the sample's magnetic or shape anisotropy. In some cases the sample's magnetization can be extracted from the measured torque. In other cases, the magnetic torque measurement is used to detect magnetic

611:

capacitor-driven magnet. One of multiple techniques must then be used to cancel out the external field from the field produced by the sample. These include counterwound coils that cancel the external uniform field and background measurements with the sample removed from the coil.

1741:

Where targets are shallow (<200 m), aeromag anomalies may be followed up with ground magnetic surveys on 10 m to 50 m line spacing with 1 m station spacing to provide the best detail (2 to 10 m pixel grid) (or 25 times the resolution prior to drilling).

1032:

Vector magnetometers are subject to temperature drift and the dimensional instability of the ferrite cores. They also require leveling to obtain component information, unlike total field (scalar) instruments. For these reasons they are no longer used for mineral exploration.

2017:

Console noise comes from magnetic components on or within the console. These include ferrite in cores in inductors and transformers, steel frames around LCDs, legs on IC chips and steel cases in disposable batteries. Some popular MIL spec connectors also have steel springs.

1012:

The caesium and potassium magnetometer's faster measurement rate allows the sensor to be moved through the area more quickly for a given number of data points. Caesium and potassium magnetometers are insensitive to rotation of the sensor while the measurement is being made.

971:

Potassium is the only optically pumped magnetometer that operates on a single, narrow electron spin resonance (ESR) line in contrast to other alkali vapour magnetometers that use irregular, composite and wide spectral lines and helium with the inherently wide spectral line.

677:, or MOKE. In this technique, incident light is directed at the sample's surface. Light interacts with a magnetized surface nonlinearly so the reflected light has an elliptical polarization, which is then measured by a detector. Another method of optical magnetometry is 750:

Magnetometers can also be classified as "AC" if they measure fields that vary relatively rapidly in time (>100 Hz), and "DC" if they measure fields that vary only slowly (quasi-static) or are static. AC magnetometers find use in electromagnetic systems (such as

1419: 2029:

The magnetic response (noise) from ferrous object on the operator and console can change with heading direction because of induction and remanence. Aeromagnetic survey aircraft and quad bike systems can use special compensators to correct for heading error noise.

1417: 1132: 1981:

In traditional mineral exploration and archaeological work, grid pegs placed by theodolite and tape measure were used to define the survey area. Some UXO surveys used ropes to define the lanes. Airborne surveys used radio triangulation beacons, such as Siledus.

1973:(UXO) location. It is twice as efficient to run a base station and use two (or more) mobile sensors to read parallel lines simultaneously (assuming data is stored and post-processed). In this manner, both along-line and cross-line gradients can be calculated. 1623:

technology to automatically record the magnetic field and their location. The data set is then corrected with data from a second magnetometer (the base station) that is left stationary and records the change in the Earth's magnetic field during the survey.

5079: 1204:

cases, the feedback current varies linearly with the external magnetic field and is used as the basis for measurement. This helps to counter inherent non-linearity between the applied external field strength and the flux gated through the sense winding.

175:

are magnetometers that measure in units of gauss or tesla, respectively. In some contexts, magnetometer is the term used for an instrument that measures fields of less than 1 millitesla (mT) and gaussmeter is used for those measuring greater than 1 mT.

1199:

There are additional factors that affect the size of the resultant signal. These factors include the number of turns in the sense winding, magnetic permeability of the core, sensor geometry, and the gated flux rate of change with respect to time.

1418: 849:

They are relatively inexpensive (< US$ 8,000) and were once widely used in mineral exploration. Three manufacturers dominate the market: GEM Systems, Geometrics and Scintrex. Popular models include G-856/857, Smartmag, GSM-18, and GSM-19T.

1137: 886:

portable units), and faster sampling as the electron-proton coupling can happen even as measurements are being taken. An Overhauser magnetometer produces readings with a 0.01 nT to 0.02 nT standard deviation while sampling once per second.

1287:

signals. Several startup companies are currently developing optically pumped magnetometers for biomedical applications: those of TwinLeaf, quSpin and FieldLine being based on alkali vapors, and those of Mag4Health on metastable helium-4.

989: 833:

Portable instruments are also limited by sensor volume (weight) and power consumption. PPMs work in field gradients up to 3,000 nT/m, which is adequate for most mineral exploration work. For higher gradient tolerance, such as mapping

1753:

target). One analogy to the resolution-with-distance is a car driving at night with lights on. At a distance of 400 m one sees one glowing haze, but as it approaches, two headlights, and then the left blinker, are visible.

1717:

Magnetometric surveys can be useful in defining magnetic anomalies which represent ore (direct detection), or in some cases gangue minerals associated with ore deposits (indirect or inferential detection). This includes

829:

For hand/backpack carried units, PPM sample rates are typically limited to less than one sample per second. Measurements are typically taken with the sensor held at fixed locations at approximately 10 metre increments.

450:, head of the Geomagnetic Observatory in Göttingen, published a paper on measurement of the Earth's magnetic field. It described a new instrument that consisted of a permanent bar magnet suspended horizontally from a 963:

signal seen at the photo detector. Again, the associated electronics use this to create a signal exactly at the frequency that corresponds to the external field. Both methods lead to high performance magnetometers.

1339:

are commonly used either in a single axis or a three axis configuration. For demanding applications a high homogeneity magnetic field is mandatory, in such cases magnetic field calibration can be performed using a

1160:

A fluxgate magnetometer consists of a small magnetically susceptible core wrapped by two coils of wire. An alternating electric current is passed through one coil, driving the core through an alternating cycle of

992:. The latter pioneered a configuration which cancels the dead-zones, which are a recurrent problem of atomic magnetometers. This configuration was demonstrated to show an accuracy of 50 pT in orbit operation. The 1317:

vapor operate similarly to the caesium magnetometers described above, yet can reach sensitivities lower than 1 fT Hz. The SERF magnetometers only operate in small magnetic fields. The Earth's field is about 50

399:

is the angular region of magnetometer orientation in which the instrument produces poor or no measurements. All optically pumped, proton-free precession, and Overhauser magnetometers experience some dead zone

1070:

sensors. These sensors produce a voltage proportional to the applied magnetic field and also sense polarity. They are used in applications where the magnetic field strength is relatively large, such as in

3958: 4458: 3918: 1136: 1133: 740:

They are also rated as "absolute" if the strength of the field can be calibrated from their own known internal constants or "relative" if they need to be calibrated by reference to a known field.

1931: 306:

is the smallest change in a magnetic field the magnetometer can resolve. A magnetometer should have a resolution a good deal smaller than the smallest change one wishes to observe. This includes

1326:

may produce a magnetic sensor that has all of its input and output signals in the form of light on fiber-optic cables. This lets the magnetic measurement be made near high electrical voltages.

853:

For mineral exploration, they have been superseded by Overhauser, caesium, and potassium instruments, all of which are fast-cycling, and do not require the operator to pause between readings.

454:

fibre. The difference in the oscillations when the bar was magnetised and when it was demagnetised allowed Gauss to calculate an absolute value for the strength of the Earth's magnetic field.

1251:, respectively). Geophysical surveys use SQUIDs from time to time, but the logistics of cooling the SQUID are much more complicated than other magnetometers that operate at room temperature. 378: 1188:

The typical fluxgate magnetometer consists of a "sense" (secondary) coil surrounding an inner "drive" (primary) coil that is closely wound around a highly permeable core material, such as

2254: 1416: 814:

are popular, and even water can be used), causing some of the protons to align themselves with that field. The current is then interrupted, and as protons realign themselves with the

1685:

Magnetometers such as the German Foerster are used to locate ferrous ordnance. Caesium and Overhauser magnetometers are used to locate and help clean up old bombing and test ranges.

5199: 1259:

Magnetometers based on atomic gasses can perform vector measurements of the magnetic field in the low field regime, where the decay of the atomic coherence becomes faster than the

1825:. Their interaction framework, called MagiTact, tracks changes to the magnetic field around a cellphone to identify different gestures made by a hand holding or wearing a magnet. 2869: 1135: 4276: 2755:

Léger, Jean-Michel; Jager, Thomas; Bertrand, François; Hulot, Gauthier; Brocco, Laura; Vigneron, Pierre; Lalanne, Xavier; Chulliat, Arnaud; Fratter, Isabelle (25 April 2015).

791:(NMR). Because the precession frequency depends only on atomic constants and the strength of the ambient magnetic field, the accuracy of this type of magnetometer can reach 1 4630: 1527:

Magnetometers are used extensively in experimental particle physics to measure the magnetic field of pivotal components such as the concentration or focusing beam-magnets.

3911: 5120: 1884: 1584:

becomes visible. A grid of magnetometers around the world constantly measures the effect of the solar wind on the Earth's magnetic field, which is then published on the

1656:

For defensive purposes, navies use arrays of magnetometers laid across sea floors in strategic locations (i.e. around ports) to monitor submarine activity. The Russian

4869: 4815: 822:

at a frequency that is directly proportional to the magnetic field. This produces a weak rotating magnetic field that is picked up by a (sometimes separate) inductor,

1985:

Non-magnetic electronic hipchain triggers were developed to trigger magnetometers. They used rotary shaft encoders to measure distance along disposable cotton reels.

212:

measure the magnitude of the vector magnetic field. Magnetometers used to study the Earth's magnetic field may express the vector components of the field in terms of

1596:

While magnetometers can be used to help map basin shape at a regional scale, they are more commonly used to map hazards to coal mining, such as basaltic intrusions (

4487: 3640: 2592: 4226: 1775:) and, more commonly, indirectly, such as by mapping geological structures conducive to mineralisation (i.e., shear zones and alteration haloes around granites). 3579:

Coleman Jr., P.J.; Davis Jr., L.; Smith, E.J.; Sonett, C.P. (1962). "The Mission of Mariner II: Preliminary Observations – Interplanetary Magnetic Fields".

4535: 3904: 1969:

Gradiometers enhance shallow magnetic anomalies and are thus good for archaeological and site investigation work. They are also good for real-time work such as

3875: 4820: 300:

set by sample rate. Modern magnetometers may perform smoothing or averaging over sequential samples, achieving a lower noise in exchange for lower bandwidth.

1000:, which was launched in 2013. An experimental vector mode, which could compete with fluxgate magnetometers was tested in this mission with overall success. 826:

electronically, and fed to a digital frequency counter whose output is typically scaled and displayed directly as field strength or output as digital data.

282:

in seconds per reading. Sample rate is important in mobile magnetometers; the sample rate and the vehicle speed determine the distance between measurements.

5558: 5507: 2055: 2054:

The Magnetometer Navigation (MAGNAV) algorithm was initially running as a flight experiment in 2004. Later on, diamond magnetometers were developed by the

3766: 4347: 4057: 2640: 556:, etc.). Measuring the magnetization as a function of temperature and magnetic field can give clues as to the type of magnetic ordering, as well as any 5593: 4618: 4574: 3887: 1134: 1996:

Magnetic surveys can suffer from noise coming from a range of sources. Different magnetometer technologies suffer different kinds of noise problems.

5011: 4453: 4251: 4246: 902:

is a highly sensitive (300 fT/Hz) and accurate device used in a wide range of applications. It is one of a number of alkali vapours (including

1016:

The lower noise of caesium and potassium magnetometers allow those measurements to more accurately show the variations in the field with position.

5203: 4929: 431: 3667: 2654: 2270: 4925: 3862: 2999: 2813: 2565: 2376: 673:

Optical magnetometry makes use of various optical techniques to measure magnetization. One such technique, Kerr magnetometry makes use of the

4462: 4281: 3835: 3816: 3797: 3750: 3508: 3201: 2549: 2524: 2389: 2264: 99: 2021:

Operators must take care to be magnetically clean and should check the 'magnetic hygiene' of all apparel and items carried during a survey.

576:

magnets. Commercial SQUID magnetometers are available for sample temperatures between 300 mK and 400 K, and magnetic fields up to 7 tesla.

228:

measure the absolute magnitude or vector magnetic field, using an internal calibration or known physical constants of the magnetic sensor.

1608:) that destroy resources and are dangerous to longwall mining equipment. Magnetometers can also locate zones ignited by lightning and map 3419: 2189: 5750: 5709: 4840: 2714:

Leger, Jean-Michel; Bertrand, François; Jager, Thomas; Le Prado, Matthieu; Fratter, Isabelle; Lalaurie, Jean-Claude (1 September 2009).

1427:

Magnetometers have a very diverse range of applications, including locating objects such as submarines, sunken ships, hazards affecting

3867: 2846:

Snare, Robert C. (1998). "A history of vector magnetometry in space". In Pfaff, Robert F.; Borovsky, Josep E.; Young, David T. (eds.).

1519: 1267:. Such zero-field optically pumped magnetometers have been tested in various configurations and with different atomic species, notably 60:. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A 4835: 4372: 3561: 1177:

consumption makes them ideal for a variety of sensing applications. Gradiometers are commonly used for archaeological prospecting and

271:

The performance and capabilities of magnetometers are described through their technical specifications. Major specifications include

4874: 4502: 4482: 4256: 2892: 1401: 2463: 5634: 4972: 4497: 4352: 4266: 3076:

Kominis, I.K.; Kornack, T.W.; Allred, J.C.; Romalis, M.V. (4 February 2003). "A subfemtotesla multichannel atomic magnetometer".

721:

A vector is a mathematical entity with both magnitude and direction. The Earth's magnetic field at a given point is a vector. A

328:

is the dependence of the measurement on temperature. It is given as a temperature coefficient in units of nT per degree Celsius.

5678: 4357: 4040: 3733:

Julie Thienel; Rick Harman; Itzhack Bar-Itzhack (2004). "Results of the Magnetometer Navigation (MAGNAV) Inflight Experiment".

3392: 2296: 1892: 1667:—by passing through large underwater loops at regular intervals—to help them escape detection by sea-floor monitoring systems, 1119: 3180:

Kitching, J.; Knappe, S.; Shah, V.; Schwindt, P.; Griffith, C.; Jimenez, R.; Preusser, J.; Liew, L. -A.; Moreland, J. (2008).

1758:

magnetisation direction (remanence) of the targets are also generally not known, and so multiple models can explain the data.

1145:

The fluxgate magnetometer was invented by H. Aschenbrenner and G. Goubau in 1936. A team at Gulf Research Laboratories led by

5745: 5564: 4897: 1911:

Systematic surveys can be used to in searching for mineral deposits or locating lost objects. Such surveys are divided into:

1807: 1383: 5131: 5624: 5394: 4987: 3473: 2679:

Hrvoic I (2008) Development of a new high sensitivity Potassium magnetometer for geophysical mapping, First Break 26:81–85

2153: 1536: 1379: 599: 3652: 3227:"The magnetic field homogeneity of coils by means of the space harmonics suppression of the current density distribution" 4735: 4612: 4549: 4472: 4342: 2131: 1903: 1837:

geologic features that make drilling impractical, and other features that give geophysicists a more complete picture of

1660:

titanium submarines were designed and built at great expense to thwart such systems (as pure titanium is non-magnetic).

3388: 3353:

Wilson, John W.; Tian, Gui Yun; Barrans, Simon (April 2007). "Residual magnetic field sensing for stress measurement".

1791: 4555: 4412: 5390: 337: 3872: 1764:

is a leading magnetic (and gravity) interpretation package used extensively in the Australian exploration industry.

5497: 4881: 4786: 2136: 788: 678: 126: 1372: 192:

orbiter for Juno can be seen here on the end of a boom. The spacecraft uses two fluxgate magnetometers. (see also

146:

quantities characterized by both strength and direction. The strength of a magnetic field is measured in units of

5735: 4861: 3644: 3304: 2909: 2113: 2098: 1668: 1620: 1345: 984:

excited to its metastable triplet state thanks to a plasma discharge have been developed in the 1960s and 70s by

878: 674: 65: 1301:

At sufficiently high atomic density, extremely high sensitivity can be achieved. Spin-exchange-relaxation-free (

747:

is a magnetometer that continuously records data over time. This data is typically represented in magnetograms.

292:

characterizes how well a magnetometer tracks rapid changes in magnetic field. For magnetometers with no onboard

79:

The first magnetometer capable of measuring the absolute magnetic intensity at a point in space was invented by

5704: 5432: 5069: 2437: 1072: 1049:

of the angle between the rotation axis of the coil and the field lines. This type of magnetometer is obsolete.

1045:. The amplitude of the signal is proportional to the strength of the field, provided it is uniform, and to the 936:

The basic principle that allows the device to operate is the fact that a caesium atom can exist in any of nine

488: 392:

is the change in the measurement due to a change in orientation of the instrument in a constant magnetic field.

2353: 713:

have the capability to measure the component of the magnetic field in a particular direction, relative to the

5699: 4958: 4601: 4018: 1888: 1850: 1796: 1064: 881:

can be exploited to significantly improve upon the proton precession magnetometer. Rather than aligning the

517: 3884: 1945:

On the base of space measured distribution of magnetic field parameters (e.g. amplitude or direction), the

334:

is the random fluctuations generated by the magnetometer sensor or electronics. Noise is given in units of

5740: 1697: 1244: 1111: 649: 57: 3270: 3226: 521: 5714: 4933: 4825: 4149: 4068: 4027: 3953: 3947: 3675: 2914: 2491:"The Beginnings of Continuous Scientific Recording using Photography: Sir Francis Ronalds' Contribution" 1565: 1428: 1162: 1094: 993: 835: 662: 466: 218:(the angle between the horizontal component of the field vector and true, or geographic, north) and the 755:), and DC magnetometers are used for detecting mineralisation and corresponding geological structures. 259:

are used to measure magnetic fields in geomagnetic surveys; they may be fixed base stations, as in the

3708: 2614: 1762: 1678:

Fluxgates can also be used in weapons navigation systems, but have been largely superseded by GPS and

406:

is the ability of a magnetometer to obtain a reliable measurement in the presence of a magnetic field

232:

measure magnitude or vector magnetic field relative to a fixed but uncalibrated baseline. Also called

5528: 5438: 4943: 4682: 4425: 4199: 4051: 3684: 3590: 3362: 3319: 3241: 3146: 3085: 2942: 2768: 2757:"In-flight performance of the Absolute Scalar Magnetometer vector mode on board the Swarm satellites" 2658: 2311: 2119: 2080: 1988:

Modern explorers use a range of low-magnetic signature GPS units, including real-time kinematic GPS.

1679: 1657: 1633: 1042: 726: 699: 491:

independently invented magnetographs in 1846 that continuously recorded the magnet's movements using

447: 255:

are used to measure the magnetic field of materials placed within them and are typically stationary.

251:

are meant to be used while in motion and may be manually carried or transported in a moving vehicle.

213: 143: 121:

In recent years, magnetometers have been miniaturized to the extent that they can be incorporated in

103: 80: 5344: 5246: 4034: 3940: 3303:

Staples, S. G. H.; Vo, C.; Cowell, D. M. J.; Freear, S.; Ives, C.; Varcoe, B. T. H. (7 April 2013).

3062: 2822: 1869: 499:

and others in a global magnetic survey and updated machines were in use well into the 20th century.

64:

is one such device, one that measures the direction of an ambient magnetic field, in this case, the

5639: 5514: 5385: 5187: 4124: 3896: 2413: 2395: 2074: 2034: 1970: 1949:

images may be generated. Such presentation of magnetic data is very useful for further analyse and

1915: 1542: 1248: 1178: 1026: 779: 769: 714: 704:

measure the total strength of the magnetic field to which they are subjected, but not its direction

686:

to control the spin of rubidium atoms which can be used to measure and monitor the magnetic field.

625: 411: 243:

are installed to a fixed position and measurements are taken while the magnetometer is stationary.

193: 5327: 5229: 5083: 5054: 4530: 3700: 3622: 3606: 3207: 3162: 3136: 3109: 2931:"High-Sensitivity Low-Noise Miniature Fluxgate Magnetometers Using a Flip Chip Conceptual Design" 2863: 2794: 2327: 1444: 1058: 997: 307: 122: 91: 4271: 2077: – Surveying method, analyzing the magnetic properties of large regions from high altitudes 1937:

Data can be divided in point located and image data, the latter of which is in ERMapper format.

1767:

Magnetometers assist mineral explorers both directly (i.e., gold mineralisation associated with

3423: 5543: 5192: 4800: 4520: 4466: 4417: 4296: 4289: 3831: 3812: 3793: 3746: 3614: 3581: 3504: 3335: 3278: 3197: 3101: 2970: 2888: 2786: 2737: 2545: 2520: 2385: 2260: 2200: 1750: 1448: 1276: 1084: 985: 737:

sensors are required to measure the components of the magnetic field in all three dimensions.

537: 293: 189: 4377: 98:

of various types, and to determine the dipole moment of magnetic materials. In an aircraft's

5755: 5453: 4214: 3738: 3692: 3598: 3370: 3327: 3249: 3189: 3154: 3093: 2960: 2950: 2851: 2776: 2772: 2727: 2319: 1818: 1260: 1169: 1124: 792: 752: 722: 708: 645: 621: 585: 557: 164: 95: 3565: 3448: 4992: 4908: 4640: 4400: 4394: 4094: 3891: 3879: 3853:

Earthquake forecasting techniques and more research on the study of electromagnetic fields

3525: 2086: 1877:

and fluxgate magnetometers. Magnetometers were also a component instrument on the Mercury

1772: 1713:, modified for aerial survey with a nose-mounted boom containing a magnetometer at its tip 1236: 1154: 1146: 682: 512: 484: 73: 68:. Other magnetometers measure the magnetic dipole moment of a magnetic material such as a 32: 2323: 3873:

Practical guidelines for building a magnetometer by hobbyists – Part 1 Introduction

3688: 3594: 3366: 3323: 3245: 3150: 3089: 2946: 2467: 2315: 917:

emitter, such as a laser, an absorption chamber containing caesium vapour mixed with a "

310:

which is caused by recording roundoff and truncation of digital expressions of the data.

4937: 4662: 4657: 4320: 4303: 4008: 2965: 2930: 2162: 2141: 1822: 1710: 1601: 1597: 1458:

Depending on the application, magnetometers can be deployed in spacecraft, aeroplanes (

1440: 1436: 1336: 1168:

A wide variety of sensors are currently available and used to measure magnetic fields.

948: 944: 470: 111: 53: 1810:(MEMS) magnetometers which are used to detect magnetic field strength and are used as 1745:

Magnetic fields from magnetic bodies of ore fall off with the inverse distance cubed (

1688:

UAV payloads also include magnetometers for a range of defensive and offensive tasks.

17: 5729: 5490: 5422: 5297: 5021: 4903: 4160: 2929:

Lu, Chih-Cheng; Huang, Jeff; Chiu, Po-Kai; Chiu, Shih-Liang; Jeng, Jen-Tzong (2014).

2331: 2125: 2068: 1946: 1800: 1641: 1605: 541: 533: 508: 496: 297: 3885:

Practical guidelines for building a magnetometer by hobbyists – Part 2 Building

3626: 3211: 3166: 2798: 2256:"Commercial magnetometers and their application", in the book "Optical Magnetometry" 2225: 5655: 5481: 5417: 5016: 4948: 4110: 3704: 3113: 1838: 1707: 1341: 1319: 1268: 1264: 1150: 937: 874: 545: 529: 474: 458: 155: 147: 3602: 2566:"MicroMicrofabricated Optically Pumped Magnetometers to Detect Source of Seizures" 2732: 2716:"Swarm Absolute Scalar and Vector Magnetometer Based on Helium 4 Optical Pumping" 2715: 3548: 2104: 2095: – Device for measuring or maintaining the orientation and angular velocity 1962: 1950: 1645: 1550: 1432: 1361: 1173: 1106: 1067: 637: 525: 492: 423: 260: 84: 69: 3790:

Signals from the Subatomic World: How to Build a Proton Precession Magnetometer

2855: 925:

pass, and a photon detector, arranged in that order. The buffer gas is usually

5290: 5277: 5167: 5160: 5026: 4998: 4675: 4668: 4646: 4568: 4337: 4220: 4190: 4143: 4136: 4104: 3696: 3374: 3193: 2781: 2756: 2384:. Warsaw: International Association of Geomagnetism and Aeronomy. p. 51. 2107: – global network of observatories, monitoring the Earth's magnetic field 1863: 1731: 1664: 1475: 918: 819: 734: 641: 633: 553: 159: 41: 37: 3339: 3282: 2790: 2741: 2490: 2414:"The Intensity of the Earth's Magnetic Force Reduced to Absolute Measurement" 2058:(AFRL) as a better method of navigation which cannot be jammed by the enemy. 733:

measures both the magnitude and direction of the total magnetic field. Three

316:

is the difference between the readings of a magnetometer true magnetic field.

5683: 5521: 5427: 5283: 5272: 5267: 5262: 5181: 5174: 5039: 5032: 5005: 4914: 4830: 4706: 4699: 4693: 4578: 4406: 4179: 4172: 4130: 4117: 4099: 4089: 4084: 4079: 4074: 4003: 3998: 3993: 3396: 3254: 2092: 1879: 1857: 1768: 1723: 1559: 1546: 1452: 1306: 1193: 1090: 907: 823: 184: 3618: 3105: 2974: 1439:, or other parameter. This helps to reveal its magnetic properties such as 1157:

by using them to measure shifts in the magnetic patterns on the sea floor.

236:, relative magnetometers are used to measure variations in magnetic field. 125:

at very low cost and are finding increasing use as miniaturized compasses (

90:

Magnetometers are widely used for measuring the Earth's magnetic field, in

815: 5607: 5600: 5469: 5125: 4688: 4508: 4233: 4166: 4154: 3988: 3983: 3978: 3020: 2910:"Victor Vacquier Sr. dies at 101; geophysicist was a master of magnetics" 2116: – Instrument for detecting variations in the Earth's magnetic field 1999:

Heading errors are one group of noise. They can come from three sources:

1727: 1719: 1609: 1314: 1189: 981: 941: 933:

and they are used to reduce collisions between the caesium vapour atoms.

930: 903: 807: 803: 799: 524:, among others. Ordering of magnetic moments are primarily classified as 407: 239:

Magnetometers may also be classified by their situation or intended use.

3742: 3141: 3097: 2144: – Electronic instrument which detects the presence of metal nearby 1075:

in cars, which sense wheel rotation speed via slots in the wheel disks.

5399: 5136: 4746: 4652: 4635: 4622: 4608: 4582: 4491: 4477: 4326: 4261: 3610: 2955: 1833: 1821:

have used magnetometers embedded in mobile devices to permit touchless

1811: 1637: 1585: 1568:. Ploughed fields behave as sources of magnetic noise in such surveys. 1386: in this section. Unsourced material may be challenged and removed. 1310: 897: 478: 440: 151: 115: 61: 3420:

Aeromagnetic Survey in Afghanistan: A Website for Distribution of Data

3331: 1640:

of the drilling tools near the drill. They are most often paired with

1149:

developed airborne fluxgate magnetometers to detect submarines during

5629: 5257: 5252: 5154: 4953: 4561: 4542: 4332: 4285: 4240: 4062: 3973: 3968: 3963: 3422:(Report). United States Geological Survey. OF 07-1247. Archived from 3158: 2022: 1746: 1581: 1272: 1231: 1225: 926: 922: 914: 882: 811: 784: 629: 549: 516:

unpaired electrons within its atoms, with smaller contributions from

3181: 3034: 2441: 1576:

Magnetometers can give an indication of auroral activity before the

2987: 2850:. Washington, D. C.: American Geophysical Union. pp. 101–114. 495:, thus easing the load on observers. They were quickly utilised by 263:

network, or mobile magnetometers used to scan a geographic region.

4920: 4856: 4362: 2641:

Requirements for obtaining high accuracy with proton magnetometers

2147: 1902: 1790: 1701: 1577: 1518: 1413: 1218: 1213: 1130: 1118: 1110: 955:

change and therefore measure the magnitude of the magnetic field.

570: 430: 422: 183: 83:

in 1833 and notable developments in the 19th century included the

31: 222:(the angle between the field vector and the horizontal surface). 4741: 4367: 4045: 3666:

Dougherty M.K.; Kellock S.; Southwood D.J.; et al. (2004).

3648: 3305:"Solving the inverse problem of magnetisation–stress resolution" 2593:"Measuring Field Strength with an Optically Pumped Magnetometer" 2128: – Physical quantity, density of magnetic moment per volume 1702: 1302: 1296: 1280: 1046: 451: 3900: 3852: 787:(hydrogen nuclei) in the magnetic field to be measured, due to 278:

is the number of readings given per second. The inverse is the

2815:

Applications of Magnetoresistive Sensors in Navigation Systems

1355: 462: 3767:"Magnetometers based on diamonds will make navigation easier" 2378:

IAGA GUIDE FOR MAGNETIC MEASUREMENTS AND OISERVAIORY PRACTICE

2226:"USGS FS–236–95: Introduction to Potential Fields: Magnetics" 3048: 3000:"Landmine and UXO detection brochure – Foerster Instruments" 2689: 2156: – scientific instrument to measure magnetic properties 1883:

mission. A magnetometer can also be used by satellites like

1009:

magnetometers have advantages over the proton magnetometer.

3857: 2253:

D. C. Hovde; M. D. Prouty; I. Hrvoic; R. E. Slocum (2013).

1907:

Ground surveying in Surprise Valley, Cedarville, California

3503:(1st ed.). Sebastopol, CA: O'Reilly. pp. 57–70. 3225:

Coillot, C.; Nativel, E.; Zanca, M.; Goze-Bac, C. (2016).

3127:

Budker, D.; Romalis, M.V. (2006). "Optical Magnetometry".

2037:

in survey images. Alternate lines can also be corrugated.

1930:

Aeromag datasets for Australia can be downloaded from the

1523:

Aust.-Synchrotron,-Quadrupole-Magnets-of-Linac,-14.06.2007

783:, PPMs or simply mags, measure the resonance frequency of 694:

Survey magnetometers can be divided into two basic types:

2352:

Tauxe, L.; Banerjee, S.K.; Butler, R.F.; van der Voo, R.

1423:

Magnetometers can measure the magnetic fields of planets.

1322:; SERF magnetometers operate in fields less than 0.5 μT. 1291:

Spin-exchange relaxation-free (SERF) atomic magnetometers

940:, which can be informally thought of as the placement of 540:(although the zoology of magnetic ordering also includes 3735:

AIAA/AAS Astrodynamics Specialist Conference and Exhibit

1873:

mission to explore Saturn. This system is composed of a

1344:, cosine coils, or calibration in the highly homogenous 1025:

total magnetic intensity, TMI) can be calculated by the

988:, then by its spinoff Polatomic, and from late 1980s by 3182:"Microfabricated atomic magnetometers and applications" 1867:

missions. A dual technique magnetometer is part of the

200:

There are two basic types of magnetometer measurement.

2354:"Essentials of Paleomagnetism: Third Web Edition 2014" 2046:

is also a hard copy and need for systematic coverage.

1181:(UXO) detection such as the German military's popular 3499:

Allan, Alasdair (2011). "5. Using the magnetometer".

2517:

Sir Francis Ronalds: Father of the Electric Telegraph

2014:

contribute small amounts to the total heading error.

1041:

The magnetic field induces a sine wave in a rotating

340: 2540:

David Gubbins; Emilio Herrero-Bervera, eds. (2007).

2158:

Pages displaying wikidata descriptions as a fallback

2109:

Pages displaying wikidata descriptions as a fallback

2089: – Measurement of ambient electromagnetic field 1263:. The physics of such magnetometers is based on the 380:, where frequency component refers to the bandwidth. 5692: 5669: 5648: 5617: 5586: 5551: 5542: 5462: 5452: 5410: 5378: 5371: 5362: 5336: 5320: 5311: 5238: 5222: 5213: 5147: 5113: 5104: 5062: 5053: 4980: 4971: 4849: 4808: 4799: 4779: 4772: 4765: 4727: 4720: 4592: 4446: 4439: 4386: 4207: 4198: 4189: 4017: 3932: 3186:

2008 IEEE International Frequency Control Symposium

2722:. Proceedings of the Eurosensors XXIII conference. 2375:JERZY JANKOWSKI & CHRISTIAN SUCKSDORFF (1996). 2122: – Diagnostic immunoassay using magnetic beads 1855:A three-axis fluxgate magnetometer was part of the 839: 565:

SQUID (superconducting quantum interference device)

204:measure the vector components of a magnetic field. 1549:, and other buried or submerged objects. Fluxgate 372: 2868:: CS1 maint: DOI inactive as of September 2024 ( 3927:Science instruments on satellites and spacecraft 2595:. National Institute of Standards and Technology 2259:. Cambridge University Press. pp. 387–405. 2071: – Device that measures proper acceleration 1619:Modern surveys generally use magnetometers with 1224:SQUID magnetometers require cooling with liquid 843: 163:of 100 nT, and magnetic field variations due to 3830:. Boca Raton, FL: CRC Press. pp. 159–256. 2542:Encyclopedia of Geomagnetism and Paleomagnetism 2495:European Society for the History of Photography 2290: 2288: 2183: 2181: 2179: 2165: – Acquisition of NMR spectra of chemicals 2101: – Accelerometer-based navigational device 373:{\displaystyle {\rm {{nT}/{\sqrt {\rm {Hz}}}}}} 2848:Measurement Techniques in Space Plasmas Fields 1749:target), or at best inverse distance squared ( 72:, for example by recording the effect of this 3912: 3551:. Portal.acm.org. Retrieved on 23 March 2011. 3418:Abraham, Jared D.; et al. (April 2008). 1063:The most common magnetic sensing devices are 644:and nearby fixed object, or by measuring the 435:Coast and Geodetic Survey Magnetometer No. 18 427:The compass is a simple type of magnetometer. 386:is the larger of the noise or the resolution. 8: 3826:Tumanski, S. (2011). "4. Magnetic sensors". 2655:"A History of Vector Magnetometry in Space" 2248: 2246: 2056:United States Air Force Research Laboratory 1895:of the magnetic field of a planet or moon. 1141:Basic principles of a fluxgate magnetometer 5548: 5459: 5375: 5368: 5317: 5219: 5110: 5059: 4977: 4805: 4776: 4769: 4724: 4443: 4204: 4195: 3919: 3905: 3897: 3668:"The Cassini magnetic field investigation" 2356:. Magnetics Information Consortium (MagIC) 1153:and after the war confirmed the theory of 628:. The most common way to measure magnetic 322:is the change in absolute error over time. 3253: 3140: 2964: 2954: 2885:Fluxgate Magnetometers for Space Research 2780: 2731: 1761:Potent by Geophysical Software Solutions 1402:Learn how and when to remove this message 1255:Zero-field optically-pumped magnetometers 802:creates a strong magnetic field around a 358: 356: 351: 343: 342: 341: 339: 3788:Hollos, Stefan; Hollos, Richard (2008). 3641:"Cassini Orbiter Instruments – MAG" 2083: – NMR use in the geomagnetic field 869:uses the same fundamental effect as the 469:was named in his honour, defined as one 36:Helium vector magnetometer (HVM) of the 2175: 1648:and azimuth of the drill can be found. 976:Metastable helium-4 scalar magnetometer 5214: 2908:Thomas H. Maugh II (24 January 2009). 2861: 1806:Many smartphones contain miniaturized 1541:Magnetometers are also used to detect 473:per square centimeter; it equals 1×10 3443: 3441: 3234:Journal of Sensors and Sensor Systems 2643:". GEM Systems Inc., 11 January 2010. 1335:feature. For this reason, coils like 838:and detecting large ferrous objects, 507:Laboratory magnetometers measure the 414:or landfills, gradients can be large. 100:attitude and heading reference system 7: 1977:Position control of magnetic surveys 1795:Tri-axis Electronic Magnetometer by 1384:adding citations to reliable sources 606:Pulsed-field extraction magnetometry 188:The Magnetometer experiment for the 167:can be in the picotesla (pT) range. 5710:Venetia Burney Student Dust Counter 1644:in drilling tools so that both the 652:off the surface of the cantilever. 595:VSM (vibrating-sample magnetometer) 3809:Magnetic sensors and magnetometers 3474:"The application of titanium Navy" 3271:"What are magnetometers, or mags?" 3021:"MicroSERF Twinleaf magnetometers" 2519:. London: Imperial College Press. 1992:Heading errors in magnetic surveys 1874: 1451:, or other properties that affect 1305:) atomic magnetometers containing 1271:(potassium, rubidium and cesium), 362: 359: 347: 344: 76:on the induced current in a coil. 25: 3828:Handbook of magnetic measurements 3524:Willie D. Jones (February 2010), 3355:Sensors and Actuators A: Physical 2041:Image processing of magnetic data 1089:These are made of thin strips of 913:The device broadly consists of a 725:is designed to give a horizontal 636:and measure the displacement via 296:, bandwidth is determined by the 114:: they can detect only magnetic ( 3449:"GMW Associates - Oil & Gas" 3395:. 1 October 2007. Archived from 2988:http://www.ti.com/lit/gpn/drv425 2887:. Norderstedt: Books on Demand. 2821:, Honeywell Inc., archived from 2639:Dr. Ivan Hrvoic, Ph.D., P.Eng. " 1360: 1115:A uniaxial fluxgate magnetometer 873:to take measurements. By adding 5679:International Lunar Observatory 4490:(TRMM, Terra, Aura, Suomi NPP, 3811:. Boston, Mass.: Artech House. 3526:"A Compass in Every Smartphone" 3393:Space Weather Prediction Center 2199:. CRC Press LLC. Archived from 1371:needs additional citations for 3269:Javaid, Maham (29 June 2022). 2324:10.1088/0953-8984/19/16/165217 1808:microelectromechanical systems 1474:), towed at a distance behind 996:chose this technology for the 877:to the measurement fluid, the 871:proton precession magnetometer 863:Overhauser effect magnetometer 857:Overhauser effect magnetometer 798:A direct current flowing in a 775:Proton precession magnetometer 764:Proton precession magnetometer 600:Vibrating-sample magnetometers 102:, they are commonly used as a 87:, which is still widely used. 27:Device that measures magnetism 1: 5625:High Resolution Stereo Camera 3603:10.1126/science.138.3545.1099 2591:Kelley, Sean (26 July 2016). 2154:Vibrating-sample magnetometer 1636:for oil or gas to detect the 1537:Magnetic survey (archaeology) 1506:Mechanical stress measurement 1462:magnetometers), helicopters ( 967:Potassium vapour magnetometer 910:) that are used in this way. 679:Faraday rotation magnetometry 110:Magnetometers can be used as 2883:Musmann, Günter Dr. (2010). 2858:(inactive 6 September 2024). 2733:10.1016/j.proche.2009.07.158 2440:. CT Systems. Archived from 2190:"Magnetic field measurement" 2150: – Type of magnetometer 2132:Magnetogram (disambiguation) 1330:Calibration of magnetometers 921:" through which the emitted 842:can handle 10,000 nT/m, and 632:is to mount the sample on a 267:Performance and capabilities 5312: 4556:Radiation Budget Instrument 3035:"quSpin QZFM magnetometers" 2621:. British Geological Survey 2438:"Magnetometer: The History" 1486:), lowered into boreholes ( 890:Caesium vapour magnetometer 5772: 5751:Nuclear magnetic resonance 4882:Infrared Space Observatory 3807:Ripka, Pavel, ed. (2001). 3312:Journal of Applied Physics 2856:10.1002/9781118664391.ch12 2297:"Advances in magnetometry" 2137:MEMS magnetic field sensor 1848: 1695: 1669:magnetic anomaly detectors 1632:Magnetometers are used in 1534: 1498:), or towed behind boats ( 1294: 1211: 1104: 1082: 1056: 1037:Rotating coil magnetometer 789:nuclear magnetic resonance 767: 656:Faraday force magnetometry 583: 568: 127:MEMS magnetic field sensor 52:is a device that measures 3868:Space-based magnetometers 3863:Earth's Field NMR (EFNMR) 3858:USGS Geomagnetism Program 3697:10.1007/s11214-004-1432-2 3375:10.1016/j.sna.2006.08.010 3194:10.1109/FREQ.2008.4623107 2782:10.1186/s40623-015-0231-1 2464:"Ferromagnetic Materials" 2304:J. Phys.: Condens. Matter 2114:Magnetic anomaly detector 2099:Inertial measurement unit 2033:Heading errors look like 1675:sonar node in the array. 1073:anti-lock braking systems 879:nuclear Overhauser effect 675:magneto-optic Kerr effect 648:of the cantilever, or by 206:Total field magnetometers 5705:Inertial Stellar Compass 5070:Raman Laser Spectrometer 3890:24 February 2021 at the 2761:Earth, Planets and Space 2295:Edelstein, Alan (2007). 1663:Military submarines are 1079:Magnetoresistive devices 1053:Hall effect magnetometer 846:can handle 30,000 nT/m. 840:Overhauser magnetometers 640:measurement between the 518:nuclear magnetic moments 503:Laboratory magnetometers 253:Laboratory magnetometers 241:Stationary magnetometers 5700:Deep Space Atomic Clock 4959:Venus Emissivity Mapper 3318:(13): 133905–133905–6. 3255:10.5194/jsss-5-401-2016 2773:2015EP&S...67...57L 1851:Spacecraft magnetometer 1612:(an impurity in coal). 980:Magnetometers based on 867:Overhauser magnetometer 3792:. Abrazol Publishing. 2515:Ronalds, B.F. (2016). 2489:Ronalds, B.F. (2016). 1908: 1803: 1714: 1698:Exploration geophysics 1564:clays, such as on the 1524: 1429:tunnel boring machines 1424: 1346:Earth's magnetic field 1245:magnetoencephalography 1142: 1128: 1116: 836:banded iron formations 650:optical interferometry 580:Inductive pickup coils 436: 428: 374: 230:Relative magnetometers 226:Absolute magnetometers 197: 66:Earth's magnetic field 58:magnetic dipole moment 45: 18:Magnetic field sensors 5746:Measuring instruments 5715:Plasma Wave Subsystem 4826:Multispectral Scanner 4150:Pioneer Venus Orbiter 3954:Pioneer Venus Orbiter 3676:Space Science Reviews 3568:on 11 September 2018. 2915:The Los Angeles Times 2690:"Polatomic - Welcome" 2310:(16): 165217 (28pp). 2188:Macintyre, Steven A. 1906: 1794: 1705: 1680:ring laser gyroscopes 1566:Great Hungarian Plain 1522: 1422: 1140: 1122: 1114: 1101:Fluxgate magnetometer 1095:magnetic permeability 844:caesium magnetometers 818:magnetic field, they 729:direction, whereas a 663:dilution refrigerator 467:magnetic flux density 434: 426: 375: 187: 180:Types of magnetometer 35: 4683:Mars Climate Orbiter 4325:RM-08 and MTVZA-OK ( 3878:10 July 2012 at the 3501:Basic sensors in iOS 3063:"Mag4Health website" 2444:on 30 September 2007 2412:Gauss, C.F. (1832). 2120:Magnetic immunoassay 2035:herringbone patterns 1887:to measure both the 1634:directional drilling 1628:Directional drilling 1543:archaeological sites 1380:improve this article 1020:Vector magnetometers 780:proton magnetometers 759:Scalar magnetometers 690:Survey magnetometers 669:Optical magnetometry 626:quantum oscillations 511:, also known as the 448:Carl Friedrich Gauss 338: 257:Survey magnetometers 249:mobile magnetometers 210:scalar magnetometers 202:Vector magnetometers 142:Magnetic fields are 81:Carl Friedrich Gauss 5640:Mars Orbiter Camera 3743:10.2514/6.2004-4749 3689:2004SSRv..114..331D 3595:1962Sci...138.1099C 3589:(3545): 1099–1100. 3480:. 15 September 2010 3367:2007SeAcA.135..381W 3324:2013JAP...113m3905S 3246:2016JSSS....5..401C 3151:2007NatPh...3..227B 3098:10.1038/nature01484 3090:2003Natur.422..596K 3049:"FieldLine website" 2947:2014Senso..1413815L 2812:Michael J. Caruso, 2619:BGS Information Hub 2316:2007JPCM...19p5217E 2197:ENG Net Base (2000) 2075:Aeromagnetic survey 2050:Aircraft navigation 1971:unexploded ordnance 1916:Aeromagnetic survey 1692:Mineral exploration 1515:Accelerator physics 1249:magnetocardiography 1179:unexploded ordnance 1163:magnetic saturation 1027:Pythagorean theorem 900:vapour magnetometer 770:Proton magnetometer 731:vector magnetometer 715:spatial orientation 615:Torque magnetometry 522:Larmor diamagnetism 419:Early magnetometers 412:unexploded ordnance 194:Magnetometer (Juno) 123:integrated circuits 92:geophysical surveys 5618:Imagers/telescopes 4766:Spectrophotometers 3478:Free press release 3426:on 26 October 2011 3399:on 22 October 2013 3275:The New York Times 2956:10.3390/s140813815 2941:(8): 13815–13829. 2720:Procedia Chemistry 1909: 1804: 1715: 1525: 1470:), on the ground ( 1445:antiferromagnetism 1425: 1208:SQUID magnetometer 1170:Fluxgate compasses 1143: 1129: 1117: 1059:Hall effect sensor 437: 429: 404:Gradient tolerance 370: 308:quantization error 198: 165:magnetic anomalies 96:magnetic anomalies 46: 5723: 5722: 5660:Rosalind Franklin 5582: 5581: 5578: 5577: 5569:Rosalind Franklin 5544:Mass spectrometer 5538: 5537: 5474:Rosalind Franklin 5448: 5447: 5358: 5357: 5354: 5353: 5307: 5306: 5215:Triaxial fluxgate 5100: 5099: 5096: 5095: 5074:Rosalind Franklin 5049: 5048: 4973:UV-visible (UVVS) 4967: 4966: 4863:Rosalind Franklin 4801:Visible-IR (VIRS) 4795: 4794: 4761: 4760: 4757: 4756: 4716: 4715: 4435: 4434: 4247:DMSP 5D-2/F13-F15 3837:978-1-4398-2952-3 3818:978-1-58053-057-6 3799:978-1-887187-09-1 3752:978-1-62410-075-8 3737:. Research Gate. 3714:on 10 August 2017 3510:978-1-4493-1542-9 3332:10.1063/1.4799049 3203:978-1-4244-1794-0 2694:www.polatomic.com 2653:Robert C. Snare. 2551:978-1-4020-3992-8 2526:978-1-78326-917-4 2391:978-0-9650686-2-8 2266:978-0-511-84638-0 2081:Earth's field NMR 1797:AKM Semiconductor 1783:recording a GPS. 1751:magnetic monopole 1449:superconductivity 1420: 1412: 1411: 1404: 1138: 1085:Magnetoresistance 986:Texas Instruments 896:optically pumped 777:s, also known as 622:phase transitions 558:phase transitions 538:antiferromagnetic 366: 326:Thermal stability 294:signal processing 16:(Redirected from 5763: 5736:Magnetic devices 5561:(Europa Clipper) 5549: 5510:(on ExoMars TGO) 5460: 5454:Neutral particle 5376: 5369: 5318: 5220: 5206:(Europa Clipper) 5111: 5060: 4978: 4806: 4777: 4770: 4725: 4721:Ultraviolet (UV) 4444: 4440:Infrared-visible 4205: 4196: 3921: 3914: 3907: 3898: 3841: 3822: 3803: 3775: 3774: 3763: 3757: 3756: 3730: 3724: 3723: 3721: 3719: 3713: 3707:. Archived from 3683:(1–4): 331–383. 3672: 3663: 3657: 3656: 3655:on 8 April 2014. 3651:. Archived from 3637: 3631: 3630: 3576: 3570: 3569: 3564:. Archived from 3558: 3552: 3546: 3540: 3539: 3538: 3536: 3521: 3515: 3514: 3496: 3490: 3489: 3487: 3485: 3470: 3464: 3463: 3461: 3459: 3445: 3436: 3435: 3433: 3431: 3415: 3409: 3408: 3406: 3404: 3385: 3379: 3378: 3350: 3344: 3343: 3309: 3300: 3294: 3293: 3291: 3289: 3266: 3260: 3259: 3257: 3231: 3222: 3216: 3215: 3177: 3171: 3170: 3159:10.1038/nphys566 3144: 3124: 3118: 3117: 3073: 3067: 3066: 3059: 3053: 3052: 3045: 3039: 3038: 3031: 3025: 3024: 3017: 3011: 3010: 3008: 3006: 2996: 2990: 2985: 2979: 2978: 2968: 2958: 2926: 2920: 2919: 2905: 2899: 2898: 2880: 2874: 2873: 2867: 2859: 2843: 2837: 2836: 2835: 2833: 2827: 2820: 2809: 2803: 2802: 2784: 2752: 2746: 2745: 2735: 2711: 2705: 2704: 2702: 2700: 2686: 2680: 2677: 2671: 2670: 2668: 2666: 2657:. Archived from 2650: 2644: 2637: 2631: 2630: 2628: 2626: 2611: 2605: 2604: 2602: 2600: 2588: 2582: 2581: 2579: 2577: 2562: 2556: 2555: 2537: 2531: 2530: 2512: 2506: 2505: 2503: 2501: 2486: 2480: 2479: 2477: 2475: 2466:. Archived from 2460: 2454: 2453: 2451: 2449: 2434: 2428: 2427: 2425: 2423: 2418: 2409: 2403: 2402: 2401:on 4 March 2016. 2400: 2394:. Archived from 2383: 2372: 2366: 2365: 2363: 2361: 2349: 2343: 2342: 2340: 2338: 2301: 2292: 2283: 2282: 2280: 2278: 2269:. Archived from 2250: 2241: 2240: 2238: 2236: 2230: 2222: 2216: 2215: 2213: 2211: 2206:on 19 March 2015 2205: 2194: 2185: 2159: 2110: 1899:Magnetic surveys 1819:Deutsche Telekom 1773:kimberlite pipes 1592:Coal exploration 1421: 1407: 1400: 1396: 1393: 1387: 1364: 1356: 1261:Larmor frequency 1242: 1234: 1139: 1125:fluxgate compass 753:magnetotellurics 723:magnetic compass 646:piezoelectricity 586:Inductive sensor 410:. In surveys of 379: 377: 376: 371: 369: 368: 367: 365: 357: 355: 350: 21: 5771: 5770: 5766: 5765: 5764: 5762: 5761: 5760: 5726: 5725: 5724: 5719: 5688: 5671: 5665: 5644: 5613: 5574: 5534: 5444: 5406: 5364: 5350: 5345:Cassini–Huygens 5332: 5303: 5247:Cassini–Huygens 5234: 5209: 5143: 5092: 5045: 4993:Mariner 6 and 7 4963: 4909:Mariner 6 and 7 4845: 4791: 4773:Long wavelength 4753: 4712: 4641:Mariner 6 and 7 4588: 4517:MESSR and VTIR 4431: 4401:Electra (radio) 4395:Cassini-Huygens 4382: 4185: 4035:Cassini–Huygens 4013: 3941:Cassini–Huygens 3928: 3925: 3892:Wayback Machine 3880:Wayback Machine 3849: 3844: 3838: 3825: 3819: 3806: 3800: 3787: 3783: 3781:Further reading 3778: 3773:. 18 July 2020. 3765: 3764: 3760: 3753: 3732: 3731: 3727: 3717: 3715: 3711: 3670: 3665: 3664: 3660: 3639: 3638: 3634: 3578: 3577: 3573: 3560: 3559: 3555: 3547: 3543: 3534: 3532: 3523: 3522: 3518: 3511: 3498: 3497: 3493: 3483: 3481: 3472: 3471: 3467: 3457: 3455: 3447: 3446: 3439: 3429: 3427: 3417: 3416: 3412: 3402: 3400: 3387: 3386: 3382: 3352: 3351: 3347: 3307: 3302: 3301: 3297: 3287: 3285: 3268: 3267: 3263: 3229: 3224: 3223: 3219: 3204: 3188:. p. 789. 3179: 3178: 3174: 3142:physics/0611246 3126: 3125: 3121: 3084:(6932): 596–9. 3075: 3074: 3070: 3061: 3060: 3056: 3047: 3046: 3042: 3033: 3032: 3028: 3019: 3018: 3014: 3004: 3002: 2998: 2997: 2993: 2986: 2982: 2928: 2927: 2923: 2907: 2906: 2902: 2895: 2882: 2881: 2877: 2860: 2845: 2844: 2840: 2831: 2829: 2825: 2818: 2811: 2810: 2806: 2754: 2753: 2749: 2713: 2712: 2708: 2698: 2696: 2688: 2687: 2683: 2678: 2674: 2664: 2662: 2652: 2651: 2647: 2638: 2634: 2624: 2622: 2613: 2612: 2608: 2598: 2596: 2590: 2589: 2585: 2575: 2573: 2572:. 17 April 2017 2564: 2563: 2559: 2552: 2539: 2538: 2534: 2527: 2514: 2513: 2509: 2499: 2497: 2488: 2487: 2483: 2473: 2471: 2470:on 27 June 2015 2462: 2461: 2457: 2447: 2445: 2436: 2435: 2431: 2421: 2419: 2416: 2411: 2410: 2406: 2398: 2392: 2381: 2374: 2373: 2369: 2359: 2357: 2351: 2350: 2346: 2336: 2334: 2299: 2294: 2293: 2286: 2276: 2274: 2273:on 7 April 2014 2267: 2252: 2251: 2244: 2234: 2232: 2228: 2224: 2223: 2219: 2209: 2207: 2203: 2192: 2187: 2186: 2177: 2173: 2168: 2157: 2108: 2087:EMF measurement 2064: 2052: 2043: 1994: 1979: 1959: 1943: 1901: 1870:Cassini–Huygens 1853: 1847: 1831: 1829:Oil exploration 1817:Researchers at 1789: 1700: 1694: 1654: 1630: 1594: 1574: 1557:The TV program 1539: 1533: 1517: 1508: 1414: 1408: 1397: 1391: 1388: 1377: 1365: 1354: 1337:Helmholtz coils 1332: 1299: 1293: 1257: 1240: 1237:liquid nitrogen 1229: 1216: 1210: 1155:plate tectonics 1147:Victor Vacquier 1131: 1109: 1103: 1087: 1081: 1061: 1055: 1039: 1022: 1006: 978: 969: 945:atomic orbitals 892: 859: 772: 766: 761: 692: 683:Meissner effect 671: 658: 617: 608: 597: 588: 582: 573: 567: 513:magnetic moment 505: 485:Francis Ronalds 421: 336: 335: 269: 182: 140: 138:Magnetic fields 135: 112:metal detectors 74:magnetic dipole 28: 23: 22: 15: 12: 11: 5: 5769: 5767: 5759: 5758: 5753: 5748: 5743: 5738: 5728: 5727: 5721: 5720: 5718: 5717: 5712: 5707: 5702: 5696: 5694: 5690: 5689: 5687: 5686: 5681: 5675: 5673: 5667: 5666: 5664: 5663: 5652: 5650: 5646: 5645: 5643: 5642: 5637: 5632: 5627: 5621: 5619: 5615: 5614: 5612: 5611: 5604: 5597: 5590: 5588: 5584: 5583: 5580: 5579: 5576: 5575: 5573: 5572: 5562: 5555: 5553: 5552:Interplanetary 5546: 5540: 5539: 5536: 5535: 5533: 5532: 5525: 5518: 5511: 5505: 5495: 5486: 5477: 5466: 5464: 5463:Interplanetary 5457: 5450: 5449: 5446: 5445: 5443: 5442: 5435: 5430: 5425: 5420: 5414: 5412: 5411:Interplanetary 5408: 5407: 5405: 5404: 5403: 5402: 5388: 5382: 5380: 5373: 5366: 5360: 5359: 5356: 5355: 5352: 5351: 5349: 5348: 5340: 5338: 5337:Interplanetary 5334: 5333: 5331: 5330: 5324: 5322: 5315: 5309: 5308: 5305: 5304: 5302: 5301: 5294: 5287: 5280: 5275: 5270: 5265: 5260: 5255: 5250: 5242: 5240: 5239:Interplanetary 5236: 5235: 5233: 5232: 5226: 5224: 5217: 5211: 5210: 5208: 5207: 5197: 5185: 5178: 5171: 5164: 5157: 5151: 5149: 5148:Interplanetary 5145: 5144: 5142: 5141: 5140: 5139: 5129: 5123: 5117: 5115: 5108: 5102: 5101: 5098: 5097: 5094: 5093: 5091: 5090: 5077: 5066: 5064: 5063:Interplanetary 5057: 5051: 5050: 5047: 5046: 5044: 5043: 5036: 5029: 5024: 5019: 5014: 5009: 5002: 4995: 4990: 4984: 4982: 4981:Interplanetary 4975: 4969: 4968: 4965: 4964: 4962: 4961: 4956: 4951: 4946: 4941: 4938:Europa Clipper 4923: 4918: 4911: 4906: 4901: 4895: 4884: 4879: 4878: 4877: 4872: 4859: 4853: 4851: 4850:Interplanetary 4847: 4846: 4844: 4843: 4838: 4833: 4828: 4823: 4818: 4812: 4810: 4803: 4797: 4796: 4793: 4792: 4790: 4789: 4783: 4781: 4780:Interplanetary 4774: 4767: 4763: 4762: 4759: 4758: 4755: 4754: 4752: 4751: 4750: 4749: 4739: 4731: 4729: 4722: 4718: 4717: 4714: 4713: 4711: 4710: 4703: 4696: 4691: 4686: 4679: 4672: 4665: 4660: 4655: 4650: 4643: 4638: 4633: 4627: 4626: 4616: 4606: 4596: 4594: 4593:Interplanetary 4590: 4589: 4587: 4586: 4572: 4565: 4558: 4553: 4546: 4539: 4533: 4528: 4527: 4526: 4523: 4515: 4512: 4505: 4500: 4495: 4485: 4480: 4475: 4470: 4456: 4450: 4448: 4441: 4437: 4436: 4433: 4432: 4430: 4429: 4422: 4410: 4403: 4398: 4390: 4388: 4387:Interplanetary 4384: 4383: 4381: 4380: 4375: 4370: 4365: 4360: 4355: 4350: 4345: 4340: 4335: 4330: 4323: 4318: 4317: 4316: 4313: 4307: 4300: 4293: 4279: 4274: 4269: 4264: 4259: 4254: 4249: 4244: 4237: 4230: 4224: 4217: 4211: 4209: 4202: 4193: 4187: 4186: 4184: 4183: 4176: 4169: 4164: 4157: 4152: 4147: 4140: 4133: 4128: 4121: 4114: 4107: 4102: 4097: 4092: 4087: 4082: 4077: 4072: 4065: 4060: 4055: 4048: 4046:ExoMars lander 4043: 4038: 4031: 4023: 4021: 4015: 4014: 4012: 4011: 4006: 4001: 3996: 3991: 3986: 3981: 3976: 3971: 3966: 3961: 3956: 3951: 3944: 3936: 3934: 3930: 3929: 3926: 3924: 3923: 3916: 3909: 3901: 3895: 3894: 3882: 3870: 3865: 3860: 3855: 3848: 3847:External links 3845: 3843: 3842: 3836: 3823: 3817: 3804: 3798: 3784: 3782: 3779: 3777: 3776: 3758: 3751: 3725: 3658: 3632: 3571: 3553: 3541: 3516: 3509: 3491: 3465: 3453:GMW Associates 3437: 3410: 3380: 3361:(2): 381–387. 3345: 3295: 3261: 3240:(2): 401–408. 3217: 3202: 3172: 3135:(4): 227–234. 3129:Nature Physics 3119: 3068: 3054: 3040: 3026: 3012: 2991: 2980: 2921: 2900: 2893: 2875: 2838: 2828:on 5 July 2010 2804: 2747: 2726:(1): 634–637. 2706: 2681: 2672: 2661:on 20 May 2012 2645: 2632: 2615:"Magnetograms" 2606: 2583: 2557: 2550: 2532: 2525: 2507: 2481: 2455: 2429: 2404: 2390: 2367: 2344: 2284: 2265: 2242: 2217: 2174: 2172: 2169: 2167: 2166: 2163:Zero field NMR 2160: 2151: 2145: 2142:Metal detector 2139: 2134: 2129: 2123: 2117: 2111: 2102: 2096: 2090: 2084: 2078: 2072: 2065: 2063: 2060: 2051: 2048: 2042: 2039: 2011: 2010: 2007: 2004: 1993: 1990: 1978: 1975: 1958: 1955: 1942: 1939: 1932:GADDS database 1928: 1927: 1924: 1921: 1918: 1900: 1897: 1849:Main article: 1846: 1843: 1830: 1827: 1823:3D interaction 1788: 1785: 1771:, diamonds in 1711:light aircraft 1696:Main article: 1693: 1690: 1653: 1650: 1642:accelerometers 1629: 1626: 1593: 1590: 1573: 1570: 1535:Main article: 1532: 1529: 1516: 1513: 1507: 1504: 1441:ferromagnetism 1437:magnetic field 1410: 1409: 1392:September 2024 1368: 1366: 1359: 1353: 1350: 1331: 1328: 1295:Main article: 1292: 1289: 1256: 1253: 1212:Main article: 1209: 1206: 1102: 1099: 1083:Main article: 1080: 1077: 1057:Main article: 1054: 1051: 1038: 1035: 1021: 1018: 1005: 1002: 977: 974: 968: 965: 949:atomic nucleus 891: 888: 858: 855: 768:Main article: 765: 762: 760: 757: 719: 718: 717:of the device. 705: 691: 688: 670: 667: 657: 654: 616: 613: 607: 604: 596: 593: 584:Main article: 581: 578: 569:Main article: 566: 563: 504: 501: 489:Charles Brooke 420: 417: 416: 415: 401: 393: 387: 381: 364: 361: 354: 349: 346: 329: 323: 317: 314:Absolute error 311: 301: 283: 268: 265: 181: 178: 139: 136: 134: 131: 54:magnetic field 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 5768: 5757: 5754: 5752: 5749: 5747: 5744: 5742: 5741:Magnetometers 5739: 5737: 5734: 5733: 5731: 5716: 5713: 5711: 5708: 5706: 5703: 5701: 5698: 5697: 5695: 5691: 5685: 5682: 5680: 5677: 5676: 5674: 5668: 5661: 5657: 5654: 5653: 5651: 5647: 5641: 5638: 5636: 5633: 5631: 5628: 5626: 5623: 5622: 5620: 5616: 5610: 5609: 5605: 5603: 5602: 5598: 5595: 5592: 5591: 5589: 5585: 5570: 5566: 5563: 5560: 5557: 5556: 5554: 5550: 5547: 5545: 5541: 5531: 5530: 5526: 5523: 5519: 5517: 5516: 5512: 5509: 5506: 5503: 5499: 5496: 5493: 5492: 5491:Venus Express 5488:ASPERA-4 (on 5487: 5484: 5483: 5479:ASPERA-3 (on 5478: 5475: 5471: 5468: 5467: 5465: 5461: 5458: 5455: 5451: 5441: 5440: 5436: 5434: 5431: 5429: 5426: 5424: 5421: 5419: 5416: 5415: 5413: 5409: 5401: 5398: 5397: 5396: 5392: 5389: 5387: 5384: 5383: 5381: 5377: 5374: 5372:Ion detectors 5370: 5367: 5361: 5347: 5346: 5342: 5341: 5339: 5335: 5329: 5326: 5325: 5323: 5319: 5316: 5314: 5310: 5300: 5299: 5298:Venus Express 5295: 5293: 5292: 5288: 5286: 5285: 5281: 5279: 5276: 5274: 5271: 5269: 5266: 5264: 5261: 5259: 5256: 5254: 5251: 5249: 5248: 5244: 5243: 5241: 5237: 5231: 5228: 5227: 5225: 5221: 5218: 5216: 5212: 5205: 5201: 5198: 5195: 5194: 5189: 5186: 5184: 5183: 5179: 5177: 5176: 5172: 5170: 5169: 5165: 5163: 5162: 5158: 5156: 5153: 5152: 5150: 5146: 5138: 5135: 5134: 5133: 5130: 5127: 5124: 5122: 5119: 5118: 5116: 5112: 5109: 5107: 5103: 5088: 5086: 5081: 5078: 5075: 5071: 5068: 5067: 5065: 5061: 5058: 5056: 5052: 5042: 5041: 5037: 5035: 5034: 5030: 5028: 5025: 5023: 5020: 5018: 5015: 5013: 5010: 5008: 5007: 5003: 5001: 5000: 4996: 4994: 4991: 4989: 4986: 4985: 4983: 4979: 4976: 4974: 4970: 4960: 4957: 4955: 4952: 4950: 4947: 4945: 4942: 4939: 4935: 4931: 4927: 4924: 4922: 4919: 4917: 4916: 4912: 4910: 4907: 4905: 4902: 4899: 4896: 4893: 4889: 4885: 4883: 4880: 4876: 4873: 4871: 4868: 4867: 4866: 4864: 4860: 4858: 4855: 4854: 4852: 4848: 4842: 4839: 4837: 4834: 4832: 4829: 4827: 4824: 4822: 4819: 4817: 4814: 4813: 4811: 4807: 4804: 4802: 4798: 4788: 4785: 4784: 4782: 4778: 4775: 4771: 4768: 4764: 4748: 4745: 4744: 4743: 4740: 4737: 4733: 4732: 4730: 4726: 4723: 4719: 4709: 4708: 4704: 4702: 4701: 4697: 4695: 4692: 4690: 4687: 4684: 4680: 4678: 4677: 4673: 4671: 4670: 4666: 4664: 4661: 4659: 4656: 4654: 4651: 4649: 4648: 4644: 4642: 4639: 4637: 4634: 4632: 4629: 4628: 4624: 4620: 4617: 4614: 4610: 4607: 4604: 4603: 4598: 4597: 4595: 4591: 4584: 4580: 4576: 4573: 4570: 4566: 4563: 4559: 4557: 4554: 4551: 4547: 4544: 4540: 4538:(Terra, Aqua) 4537: 4534: 4532: 4529: 4524: 4522: 4519: 4518: 4516: 4513: 4510: 4506: 4504: 4501: 4499: 4496: 4493: 4489: 4486: 4484: 4481: 4479: 4476: 4474: 4471: 4468: 4464: 4460: 4457: 4455: 4452: 4451: 4449: 4445: 4442: 4438: 4428: 4427: 4423: 4420: 4419: 4414: 4411: 4409: 4408: 4404: 4402: 4399: 4397: 4396: 4392: 4391: 4389: 4385: 4379: 4376: 4374: 4371: 4369: 4366: 4364: 4361: 4359: 4356: 4354: 4351: 4349: 4346: 4344: 4341: 4339: 4336: 4334: 4331: 4328: 4324: 4322: 4319: 4314: 4311: 4310: 4308: 4305: 4301: 4298: 4294: 4291: 4287: 4283: 4280: 4278: 4275: 4273: 4270: 4268: 4265: 4263: 4260: 4258: 4255: 4253: 4252:DMSP 5D-2/F16 4250: 4248: 4245: 4242: 4238: 4235: 4231: 4228: 4225: 4222: 4218: 4216: 4213: 4212: 4210: 4206: 4203: 4201: 4197: 4194: 4192: 4188: 4182: 4181: 4177: 4175: 4174: 4170: 4168: 4165: 4163: 4162: 4161:Venus Express 4158: 4156: 4153: 4151: 4148: 4146: 4145: 4141: 4139: 4138: 4134: 4132: 4129: 4127: 4126: 4122: 4120: 4119: 4115: 4113: 4112: 4108: 4106: 4103: 4101: 4098: 4096: 4093: 4091: 4088: 4086: 4083: 4081: 4078: 4076: 4073: 4071: 4070: 4066: 4064: 4061: 4059: 4056: 4054: 4053: 4049: 4047: 4044: 4042: 4039: 4037: 4036: 4032: 4030: 4029: 4025: 4024: 4022: 4020: 4019:Radio science 4016: 4010: 4007: 4005: 4002: 4000: 3997: 3995: 3992: 3990: 3987: 3985: 3982: 3980: 3977: 3975: 3972: 3970: 3967: 3965: 3962: 3960: 3957: 3955: 3952: 3950: 3949: 3945: 3943: 3942: 3938: 3937: 3935: 3931: 3922: 3917: 3915: 3910: 3908: 3903: 3902: 3899: 3893: 3889: 3886: 3883: 3881: 3877: 3874: 3871: 3869: 3866: 3864: 3861: 3859: 3856: 3854: 3851: 3850: 3846: 3839: 3833: 3829: 3824: 3820: 3814: 3810: 3805: 3801: 3795: 3791: 3786: 3785: 3780: 3772: 3771:The Economist 3768: 3762: 3759: 3754: 3748: 3744: 3740: 3736: 3729: 3726: 3710: 3706: 3702: 3698: 3694: 3690: 3686: 3682: 3678: 3677: 3669: 3662: 3659: 3654: 3650: 3646: 3642: 3636: 3633: 3628: 3624: 3620: 3616: 3612: 3608: 3604: 3600: 3596: 3592: 3588: 3584: 3583: 3575: 3572: 3567: 3563: 3557: 3554: 3550: 3545: 3542: 3531: 3530:IEEE Spectrum 3527: 3520: 3517: 3512: 3506: 3502: 3495: 3492: 3479: 3475: 3469: 3466: 3454: 3450: 3444: 3442: 3438: 3425: 3421: 3414: 3411: 3398: 3394: 3390: 3389:"The K-index" 3384: 3381: 3376: 3372: 3368: 3364: 3360: 3356: 3349: 3346: 3341: 3337: 3333: 3329: 3325: 3321: 3317: 3313: 3306: 3299: 3296: 3284: 3280: 3276: 3272: 3265: 3262: 3256: 3251: 3247: 3243: 3239: 3235: 3228: 3221: 3218: 3213: 3209: 3205: 3199: 3195: 3191: 3187: 3183: 3176: 3173: 3168: 3164: 3160: 3156: 3152: 3148: 3143: 3138: 3134: 3130: 3123: 3120: 3115: 3111: 3107: 3103: 3099: 3095: 3091: 3087: 3083: 3079: 3072: 3069: 3064: 3058: 3055: 3050: 3044: 3041: 3036: 3030: 3027: 3022: 3016: 3013: 3001: 2995: 2992: 2989: 2984: 2981: 2976: 2972: 2967: 2962: 2957: 2952: 2948: 2944: 2940: 2936: 2932: 2925: 2922: 2917: 2916: 2911: 2904: 2901: 2896: 2894:9783839137024 2890: 2886: 2879: 2876: 2871: 2865: 2857: 2853: 2849: 2842: 2839: 2824: 2817: 2816: 2808: 2805: 2800: 2796: 2792: 2788: 2783: 2778: 2774: 2770: 2766: 2762: 2758: 2751: 2748: 2743: 2739: 2734: 2729: 2725: 2721: 2717: 2710: 2707: 2695: 2691: 2685: 2682: 2676: 2673: 2660: 2656: 2649: 2646: 2642: 2636: 2633: 2620: 2616: 2610: 2607: 2594: 2587: 2584: 2571: 2567: 2561: 2558: 2553: 2547: 2543: 2536: 2533: 2528: 2522: 2518: 2511: 2508: 2496: 2492: 2485: 2482: 2469: 2465: 2459: 2456: 2443: 2439: 2433: 2430: 2415: 2408: 2405: 2397: 2393: 2387: 2380: 2379: 2371: 2368: 2355: 2348: 2345: 2333: 2329: 2325: 2321: 2317: 2313: 2309: 2305: 2298: 2291: 2289: 2285: 2272: 2268: 2262: 2258: 2257: 2249: 2247: 2243: 2227: 2221: 2218: 2202: 2198: 2191: 2184: 2182: 2180: 2176: 2170: 2164: 2161: 2155: 2152: 2149: 2146: 2143: 2140: 2138: 2135: 2133: 2130: 2127: 2126:Magnetization 2124: 2121: 2118: 2115: 2112: 2106: 2103: 2100: 2097: 2094: 2091: 2088: 2085: 2082: 2079: 2076: 2073: 2070: 2069:Accelerometer 2067: 2066: 2061: 2059: 2057: 2049: 2047: 2040: 2038: 2036: 2031: 2027: 2026:problematic. 2024: 2019: 2015: 2008: 2005: 2002: 2001: 2000: 1997: 1991: 1989: 1986: 1983: 1976: 1974: 1972: 1967: 1964: 1956: 1954: 1952: 1948: 1947:magnetovision 1941:Magnetovision 1940: 1938: 1935: 1933: 1925: 1922: 1919: 1917: 1914: 1913: 1912: 1905: 1898: 1896: 1894: 1890: 1886: 1882: 1881: 1876: 1875:vector helium 1872: 1871: 1866: 1865: 1860: 1859: 1852: 1844: 1842: 1840: 1835: 1828: 1826: 1824: 1820: 1815: 1813: 1809: 1802: 1801:Motorola Xoom 1798: 1793: 1787:Mobile phones 1786: 1784: 1780: 1776: 1774: 1770: 1765: 1763: 1759: 1755: 1752: 1748: 1743: 1739: 1735: 1733: 1729: 1725: 1721: 1712: 1709: 1704: 1699: 1691: 1689: 1686: 1683: 1681: 1676: 1672: 1670: 1666: 1661: 1659: 1651: 1649: 1647: 1643: 1639: 1635: 1627: 1625: 1622: 1617: 1613: 1611: 1607: 1606:volcanic plug 1603: 1599: 1591: 1589: 1587: 1583: 1579: 1571: 1569: 1567: 1562: 1561: 1555: 1552: 1548: 1544: 1538: 1530: 1528: 1521: 1514: 1512: 1505: 1503: 1501: 1497: 1493: 1489: 1485: 1481: 1478:(ATVs) on a ( 1477: 1473: 1469: 1465: 1461: 1456: 1454: 1450: 1446: 1442: 1438: 1434: 1430: 1406: 1403: 1395: 1385: 1381: 1375: 1374: 1369:This section 1367: 1363: 1358: 1357: 1351: 1349: 1347: 1343: 1338: 1329: 1327: 1323: 1321: 1316: 1312: 1308: 1304: 1298: 1290: 1288: 1284: 1282: 1278: 1274: 1270: 1266: 1262: 1254: 1252: 1250: 1246: 1238: 1233: 1227: 1222: 1220: 1215: 1207: 1205: 1201: 1197: 1195: 1191: 1186: 1184: 1180: 1175: 1171: 1166: 1164: 1158: 1156: 1152: 1148: 1127:/inclinometer 1126: 1121: 1113: 1108: 1100: 1098: 1096: 1092: 1086: 1078: 1076: 1074: 1069: 1066: 1060: 1052: 1050: 1048: 1044: 1036: 1034: 1030: 1028: 1019: 1017: 1014: 1010: 1003: 1001: 999: 998:Swarm mission 995: 991: 987: 983: 975: 973: 966: 964: 960: 956: 952: 950: 946: 943: 939: 938:energy levels 934: 932: 928: 924: 920: 916: 911: 909: 905: 901: 899: 889: 887: 884: 880: 876: 875:free radicals 872: 868: 864: 856: 854: 851: 847: 845: 841: 837: 831: 827: 825: 821: 817: 813: 809: 806:-rich fluid ( 805: 801: 796: 794: 790: 786: 782: 781: 776: 771: 763: 758: 756: 754: 748: 746: 741: 738: 736: 732: 728: 724: 716: 712: 711:magnetometers 710: 706: 703: 702:magnetometers 701: 697: 696: 695: 689: 687: 684: 680: 676: 668: 666: 664: 655: 653: 651: 647: 643: 639: 635: 631: 627: 623: 614: 612: 605: 603: 601: 594: 592: 587: 579: 577: 572: 564: 562: 559: 555: 551: 547: 543: 542:ferrimagnetic 539: 535: 534:ferromagnetic 531: 527: 523: 519: 514: 510: 509:magnetization 502: 500: 498: 497:Edward Sabine 494: 490: 486: 482: 480: 476: 472: 468: 464: 460: 455: 453: 449: 444: 442: 433: 425: 418: 413: 409: 405: 402: 398: 394: 391: 390:Heading error 388: 385: 382: 352: 333: 330: 327: 324: 321: 318: 315: 312: 309: 305: 302: 299: 298:Nyquist limit 295: 291: 287: 284: 281: 277: 274: 273: 272: 266: 264: 262: 258: 254: 250: 246: 242: 237: 235: 231: 227: 223: 221: 217: 216: 211: 207: 203: 195: 191: 186: 179: 177: 174: 170: 166: 161: 157: 153: 149: 145: 137: 132: 130: 128: 124: 119: 117: 113: 108: 105: 101: 97: 93: 88: 86: 82: 77: 75: 71: 67: 63: 59: 55: 51: 43: 39: 34: 30: 19: 5670:Astronomical 5659: 5656:MicrOmega-IR 5606: 5599: 5596:(on InSight) 5587:Seismometers 5568: 5527: 5513: 5501: 5489: 5482:Mars Express 5480: 5473: 5437: 5343: 5313:Helium vapor 5296: 5289: 5282: 5245: 5191: 5180: 5173: 5166: 5159: 5106:Magnetometer 5105: 5085:Perseverance 5084: 5073: 5038: 5031: 5004: 4997: 4913: 4891: 4887: 4862: 4705: 4698: 4674: 4667: 4645: 4602:Schiaparelli 4600: 4599:COMARS+ (on 4514:Kanopus-V-IK 4424: 4416: 4405: 4393: 4178: 4171: 4159: 4142: 4135: 4123: 4116: 4111:Mars Express 4109: 4067: 4050: 4033: 4026: 3946: 3939: 3827: 3808: 3789: 3770: 3761: 3734: 3728: 3716:. Retrieved 3709:the original 3680: 3674: 3661: 3653:the original 3635: 3586: 3580: 3574: 3566:the original 3556: 3544: 3533:, retrieved 3529: 3519: 3500: 3494: 3482:. Retrieved 3477: 3468: 3456:. Retrieved 3452: 3428:. Retrieved 3424:the original 3413: 3401:. Retrieved 3397:the original 3383: 3358: 3354: 3348: 3315: 3311: 3298: 3286:. Retrieved 3274: 3264: 3237: 3233: 3220: 3185: 3175: 3132: 3128: 3122: 3081: 3077: 3071: 3057: 3043: 3029: 3015: 3003:. Retrieved 2994: 2983: 2938: 2934: 2924: 2913: 2903: 2884: 2878: 2847: 2841: 2830:, retrieved 2823:the original 2814: 2807: 2764: 2760: 2750: 2723: 2719: 2709: 2697:. Retrieved 2693: 2684: 2675: 2663:. Retrieved 2659:the original 2648: 2635: 2623:. Retrieved 2618: 2609: 2597:. Retrieved 2586: 2574:. Retrieved 2569: 2560: 2544:. Springer. 2541: 2535: 2516: 2510: 2498:. Retrieved 2494: 2484: 2472:. Retrieved 2468:the original 2458: 2446:. Retrieved 2442:the original 2432: 2420:. Retrieved 2407: 2396:the original 2377: 2370: 2358:. Retrieved 2347: 2335:. Retrieved 2307: 2303: 2275:. Retrieved 2271:the original 2255: 2233:. Retrieved 2220: 2208:. Retrieved 2201:the original 2196: 2053: 2044: 2032: 2028: 2020: 2016: 2012: 1998: 1995: 1987: 1984: 1980: 1968: 1963:gradiometers 1960: 1944: 1936: 1929: 1910: 1878: 1868: 1862: 1856: 1854: 1839:stratigraphy 1832: 1816: 1805: 1781: 1777: 1766: 1760: 1756: 1744: 1740: 1736: 1730:, and often 1716: 1708:Diamond DA42 1687: 1684: 1677: 1673: 1662: 1655: 1631: 1618: 1614: 1595: 1575: 1558: 1556: 1551:gradiometers 1540: 1526: 1509: 1499: 1495: 1491: 1487: 1483: 1479: 1471: 1467: 1463: 1459: 1457: 1426: 1398: 1389: 1378:Please help 1373:verification 1370: 1342:Maxwell coil 1333: 1324: 1300: 1285: 1265:Hanle effect 1258: 1223: 1217: 1202: 1198: 1187: 1182: 1174:gradiometers 1167: 1159: 1151:World War II 1144: 1088: 1062: 1040: 1031: 1023: 1015: 1011: 1007: 1004:Applications 979: 970: 961: 957: 953: 935: 912: 895: 893: 870: 866: 862: 860: 852: 848: 832: 828: 797: 778: 774: 773: 749: 745:magnetograph 744: 742: 739: 730: 720: 707: 698: 693: 672: 659: 618: 609: 598: 589: 574: 546:helimagnetic 530:paramagnetic 506: 483: 456: 445: 438: 403: 396: 389: 383: 331: 325: 319: 313: 303: 289: 285: 279: 275: 270: 256: 252: 248: 244: 240: 238: 233: 229: 225: 224: 219: 214: 209: 205: 201: 199: 172: 168: 141: 133:Introduction 120: 109: 94:, to detect 89: 78: 50:magnetometer 49: 47: 29: 5672:instruments 5649:Microscopes 4315:Meteor-M2-1 4304:Meteor-3M-1 2105:Intermagnet 1957:Gradiometer 1951:data fusion 1646:inclination 1531:Archaeology 1433:temperature 1281:SERF effect 1107:Gradiometer 1068:Hall effect 1065:solid-state 947:around the 638:capacitance 526:diamagnetic 493:photography 384:Sensitivity 276:Sample rate 261:INTERMAGNET 234:variometers 220:inclination 215:declination 173:teslameters 169:Gaussmeters 85:Hall effect 70:ferromagnet 5730:Categories 5379:Near-Earth 5321:Near-Earth 5291:Pioneer 11 5223:Near-Earth 5161:Pioneer 10 5114:Near-Earth 4999:Mariner 10 4809:Near-Earth 4728:Near-Earth 4681:PMIRR (on 4669:Pioneer 10 4647:Mariner 10 4569:Sentinel-3 4447:Near-Earth 4338:Sentinel-3 4309:MTVZA-GYa 4272:Kanopus-ST 4221:Sentinel-6 4208:Near-Earth 4191:Radiometer 4041:Europa-UVS 3718:1 November 3562:"中国科技论文在线" 3535:21 October 3484:9 December 3403:21 October 3005:25 October 2832:21 October 2665:25 October 2625:5 December 2448:21 October 2422:21 October 2171:References 1864:Mariner 10 1845:Spacecraft 1732:pyrrhotite 1658:Alfa-class 1547:shipwrecks 1476:quad bikes 1460:fixed wing 1105:See also: 919:buffer gas 735:orthogonal 642:cantilever 634:cantilever 554:spin glass 304:Resolution 280:cycle time 160:cgs system 44:spacecraft 38:Pioneer 10 5684:MoonLIGHT 5522:Mariner 2 5502:Curiosity 5428:Mariner 2 5365:detectors 5284:MESSENGER 5263:Mariner 2 5175:Voyager 1 5033:Voyager 1 5006:MESSENGER 4915:MESSENGER 4900:(on Juno) 4888:Voyager 1 4831:SCIAMACHY 4700:Voyager 1 4663:2M No.522 4658:2M No.521 4579:Suomi NPP 4407:Mariner 2 4312:Meteor-M2 4299:, MOS-1b) 4200:Microwave 4173:Voyager 1 4131:Pioneer 7 4118:MESSENGER 4075:Mariner 2 3430:25 August 3340:0021-8979 3283:0362-4331 2864:cite book 2791:1880-5981 2767:(1): 57. 2742:1876-6196 2570:Medgadget 2332:108531365 2093:Gyroscope 1961:Magnetic 1893:direction 1889:magnitude 1880:MESSENGER 1858:Mariner 2 1812:compasses 1799:, inside 1769:magnetite 1724:magnetite 1665:degaussed 1580:from the 1560:Time Team 1453:magnetism 1307:potassium 1241:77 K 1230:4.2 1194:permalloy 1093:, a high 1091:Permalloy 908:potassium 824:amplified 446:In 1833, 397:dead zone 286:Bandwidth 154:, and in 5601:Viking 1 5520:SPS (on 5470:ADRON-RM 5456:detector 5423:ASPERA-4 5418:ASPERA-3 5363:Particle 5126:QuakeSat 4926:E-THEMIS 4689:Venera 9 4531:Meteor-2 4509:ADEOS II 4321:Nimbus 7 4267:GPM Core 4234:ADEOS II 4167:Venera 9 4155:Sakigake 4069:Magellan 4028:Akatsuki 3979:Venera 4 3948:Magellan 3888:Archived 3876:Archived 3627:19708490 3619:17772967 3549:MagiTact 3458:16 March 3288:7 August 3212:46471890 3167:96446612 3106:12686995 2975:25196107 2799:55990684 2599:18 April 2576:18 April 2360:30 March 2337:29 March 2277:30 March 2235:29 March 2210:29 March 2062:See also 2009:Operator 1920:Borehole 1728:hematite 1720:iron ore 1652:Military 1610:siderite 1500:tow fish 1472:backpack 1315:rubidium 1190:mu-metal 1183:Foerster 990:CEA-Leti 982:helium-4 942:electron 931:nitrogen 904:rubidium 808:kerosene 804:hydrogen 800:solenoid 550:toroidal 465:unit of 408:gradient 400:effects. 290:bandpass 245:Portable 152:SI units 5756:Sensors 5529:Ulysses 5439:Ulysses 5400:Proba-2 5386:DEMETER 5137:Proba-2 5128:1 and 2 5080:SHERLOC 4870:MA-MISS 4747:Proba-2 4653:Mars 96 4636:Luna 13 4623:InSight 4609:Diviner 4583:NOAA-21 4567:SLSTR ( 4492:NOAA-20 4483:AVNIR-2 4426:Rosetta 4378:Zond-PP 4327:Sich-1M 4302:MTVZA ( 4262:Envisat 4241:Shizuku 4239:AMSR2 ( 4219:AMR-C ( 4058:InSight 4052:Galileo 3705:3035894 3685:Bibcode 3611:1709490 3591:Bibcode 3582:Science 3363:Bibcode 3320:Bibcode 3242:Bibcode 3147:Bibcode 3114:4204465 3086:Bibcode 2966:4179035 2943:Bibcode 2935:Sensors 2769:Bibcode 2312:Bibcode 2006:Console 1834:Seismic 1638:azimuth 1586:K-index 1572:Auroras 1484:trailer 1464:stinger 1311:caesium 1277:mercury 923:photons 898:caesium 883:protons 820:precess 816:ambient 785:protons 727:bearing 479:SI unit 471:maxwell 441:compass 158:in the 150:in the 116:ferrous 104:heading 62:compass 5662:rover) 5630:HiRISE 5571:rover) 5559:MASPEX 5515:Nozomi 5476:rover) 5258:Magsat 5253:FIELDS 5200:ICEMAG 5155:FIELDS 5076:rover) 5022:SPICAV 5017:SPICAM 4954:SPICAV 4949:SPICAM 4886:IRIS ( 4736:EURECA 4562:GCOM-C 4560:SGLI ( 4550:EURECA 4543:JERS-1 4333:Seasat 4286:MOPITT 4232:AMSR ( 4229:(AQUA) 4227:AMSR-E 4125:Nozomi 4063:Kaguya 4009:WISDOM 3974:MARSIS 3969:SHARAD 3964:SELENE 3959:REASON 3834: 3815: 3796: 3749: 3703: 3625: 3617: 3609: 3507: 3338: 3281: 3210: 3200: 3165: 3112: 3104: 3078:Nature 2973: 2963: 2891: 2797: 2789: 2740: 2699:11 May 2548: 2523: 2500:2 June 2474:26 May 2388: 2330: 2263: 2231:. USGS 2023:Akubra 2003:Sensor 1926:Marine 1923:Ground 1747:dipole 1604:, and 1582:aurora 1492:probe, 1273:helium 1269:alkali 1226:helium 1219:SQUIDs 927:helium 915:photon 812:decane 709:Vector 700:Scalar 630:torque 461:, the 144:vector 5635:LORRI 5508:FREND 5328:Swarm 5230:Swarm 5087:rover 5055:Raman 5012:NOMAD 4988:Alice 4944:Ralph 4921:MERIS 4898:JIRAM 4865:rover 4857:AKARI 4734:ORI ( 4575:VIIRS 4548:ORI ( 4541:OPS ( 4536:MODIS 4521:MOS-1 4507:GLI ( 4488:CERES 4478:AVNIR 4467:Terra 4459:ASTER 4454:AVHRR 4373:WSF-M 4363:SSMIS 4358:SSM/I 4297:MOS-1 4295:MSR ( 4290:Terra 4277:MIRAS 3933:Radar 3712:(PDF) 3701:S2CID 3671:(PDF) 3623:S2CID 3607:JSTOR 3308:(PDF) 3230:(PDF) 3208:S2CID 3163:S2CID 3137:arXiv 3110:S2CID 2826:(PDF) 2819:(PDF) 2795:S2CID 2417:(PDF) 2399:(PDF) 2382:(PDF) 2328:S2CID 2300:(PDF) 2229:(PDF) 2204:(PDF) 2193:(PDF) 2148:SQUID 1602:sills 1598:dykes 1578:light 1496:sonde 1313:, or 1235:) or 1214:SQUID 571:SQUID 536:, or 477:(the 475:tesla 459:gauss 332:Noise 320:Drift 156:gauss 148:tesla 5693:Misc 5594:SEIS 5565:MOMA 5500:(on 5395:DSLP 5393:and 5391:TPMU 5204:PIMS 5202:and 5193:Juno 5132:SGVM 5121:GOES 4936:(on 4934:SUDA 4930:MISE 4890:and 4875:ISEM 4841:TRMM 4821:MOMS 4816:CASE 4742:LYRA 4631:IRIS 4621:(on 4611:(on 4503:ERSS 4498:ERBS 4473:AIRS 4463:MISR 4418:Juno 4368:TRMM 4353:SMOS 4348:SMMR 4343:SMAP 4282:MISR 4257:ERSS 4215:AQUA 4095:6, 7 3832:ISBN 3813:ISBN 3794:ISBN 3747:ISBN 3720:2017 3649:NASA 3615:PMID 3537:2012 3505:ISBN 3486:2013 3460:2022 3432:2011 3405:2009 3336:ISSN 3290:2024 3279:ISSN 3198:ISBN 3102:PMID 3007:2012 2971:PMID 2889:ISBN 2870:link 2834:2012 2787:ISSN 2738:ISSN 2701:2022 2667:2012 2627:2022 2601:2017 2578:2017 2546:ISBN 2521:ISBN 2502:2016 2476:2015 2450:2009 2424:2009 2386:ISBN 2362:2014 2339:2014 2279:2014 2261:ISBN 2237:2014 2212:2014 1891:and 1885:GOES 1861:and 1488:tool 1480:sled 1468:bird 1466:and 1352:Uses 1303:SERF 1297:SERF 1275:and 1247:and 1172:and 1047:sine 1043:coil 906:and 894:The 861:The 810:and 487:and 457:The 452:gold 439:The 395:The 190:Juno 171:and 40:and 5498:DAN 5433:SPS 5188:MAG 5027:UVS 4836:TES 4787:ISO 4619:HP3 4613:LRO 4413:MWR 3739:doi 3693:doi 3681:114 3645:JPL 3599:doi 3587:138 3371:doi 3359:135 3328:doi 3316:113 3250:doi 3190:doi 3155:doi 3094:doi 3082:422 2961:PMC 2951:doi 2852:doi 2777:doi 2728:doi 2320:doi 1621:GPS 1502:). 1494:or 1482:or 1382:by 1192:or 994:ESA 929:or 865:or 793:ppm 624:or 481:). 463:CGS 288:or 247:or 208:or 129:). 56:or 5732:: 5278:10 5168:11 4932:, 4928:, 4694:10 4676:11 4581:, 4525:1b 4461:, 4284:, 4144:11 4137:10 4105:10 4004:16 3999:15 3994:10 3769:. 3745:. 3699:. 3691:. 3679:. 3673:. 3643:. 3621:. 3613:. 3605:. 3597:. 3585:. 3528:, 3476:. 3451:. 3440:^ 3391:. 3369:. 3357:. 3334:. 3326:. 3314:. 3310:. 3277:. 3273:. 3248:. 3236:. 3232:. 3206:. 3196:. 3184:. 3161:. 3153:. 3145:. 3131:. 3108:. 3100:. 3092:. 3080:. 2969:. 2959:. 2949:. 2939:14 2937:. 2933:. 2912:. 2866:}} 2862:{{ 2793:. 2785:. 2775:. 2765:67 2763:. 2759:. 2736:. 2718:. 2692:. 2617:. 2568:. 2493:. 2326:. 2318:. 2308:19 2306:. 2302:. 2287:^ 2245:^ 2195:. 2178:^ 1953:. 1934:. 1841:. 1734:. 1726:, 1722:, 1706:A 1682:. 1600:, 1588:. 1545:, 1490:, 1455:. 1447:, 1443:, 1435:, 1348:. 1320:μT 1309:, 1283:. 1185:. 1123:A 1029:. 795:. 743:A 552:, 548:, 544:, 532:, 528:, 520:, 48:A 42:11 5658:( 5608:2 5567:( 5524:) 5504:) 5494:) 5485:) 5472:( 5273:5 5268:4 5196:) 5190:( 5182:2 5089:) 5082:( 5072:( 5040:2 4940:) 4904:M 4894:) 4892:2 4738:) 4707:2 4685:) 4625:) 4615:) 4605:) 4585:) 4577:( 4571:) 4564:) 4552:) 4545:) 4511:) 4494:) 4469:) 4465:( 4421:) 4415:( 4329:) 4306:) 4292:) 4288:( 4243:) 4236:) 4223:) 4180:2 4100:9 4090:5 4085:4 4080:3 3989:9 3984:8 3920:e 3913:t 3906:v 3840:. 3821:. 3802:. 3755:. 3741:: 3722:. 3695:: 3687:: 3647:/ 3629:. 3601:: 3593:: 3513:. 3488:. 3462:. 3434:. 3407:. 3377:. 3373:: 3365:: 3342:. 3330:: 3322:: 3292:. 3258:. 3252:: 3244:: 3238:5 3214:. 3192:: 3169:. 3157:: 3149:: 3139:: 3133:3 3116:. 3096:: 3088:: 3065:. 3051:. 3037:. 3023:. 3009:. 2977:. 2953:: 2945:: 2918:. 2897:. 2872:) 2854:: 2801:. 2779:: 2771:: 2744:. 2730:: 2724:1 2703:. 2669:. 2629:. 2603:. 2580:. 2554:. 2529:. 2504:. 2478:. 2452:. 2426:. 2364:. 2341:. 2322:: 2314:: 2281:. 2239:. 2214:. 1405:) 1399:( 1394:) 1390:( 1376:. 1239:( 1232:K 1228:( 363:z 360:H 353:/ 348:T 345:n 196:) 20:)

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

Index