339:. Consequently, one of astronomy's central challenges in determining a star's luminosity is to derive accurate measurements for each of these components, without which an accurate luminosity figure remains elusive. Extinction can only be measured directly if the actual and observed luminosities are both known, but it can be estimated from the observed colour of a star, using models of the expected level of reddening from the interstellar medium.
40:
863:
810:
2562:
2586:
2538:
2574:
320:. However, for most stars the angular diameter or parallax, or both, are far below our ability to measure with any certainty. Since the effective temperature is merely a number that represents the temperature of a black body that would reproduce the luminosity, it obviously cannot be measured directly, but it can be estimated from the spectrum.
2550:
375:
are found above and to the right of the main sequence, more luminous or cooler than their equivalents on the main sequence. Increased luminosity at the same temperature, or alternatively cooler temperature at the same luminosity, indicates that these stars are larger than those on the main sequence
358:
stars exhibit temperatures less than 3,500 K. Because luminosity is proportional to temperature to the fourth power, the large variation in stellar temperatures produces an even vaster variation in stellar luminosity. Because the luminosity depends on a high power of the stellar mass, high mass
245:
While bolometers do exist, they cannot be used to measure even the apparent brightness of a star because they are insufficiently sensitive across the electromagnetic spectrum and because most wavelengths do not reach the surface of the Earth. In practice bolometric magnitudes are measured by taking
1327:
In measuring star brightnesses, absolute magnitude, apparent magnitude, and distance are interrelated parameters—if two are known, the third can be determined. Since the Sun's luminosity is the standard, comparing these parameters with the Sun's apparent magnitude and distance is the easiest way to
773:
To calculate the total radio power, this luminosity must be integrated over the bandwidth of the emission. A common assumption is to set the bandwidth to the observing frequency, which effectively assumes the power radiated has uniform intensity from zero frequency up to the observing frequency. In
1966:
Mamajek, E. E.; Prsa, A.; Torres, G.; Harmanec, P.; Asplund, M.; Bennett, P. D.; Capitaine, N.; Christensen-Dalsgaard, J.; Depagne, E.; Folkner, W. M.; Haberreiter, M.; Hekker, S.; Hilton, J. L.; Kostov, V.; Kurtz, D. W.; Laskar, J.; Mason, B. D.; Milone, E. F.; Montgomery, M. M.; Richards, M. T.;
246:
measurements at certain wavelengths and constructing a model of the total spectrum that is most likely to match those measurements. In some cases, the process of estimation is extreme, with luminosities being calculated when less than 1% of the energy output is observed, for example with a hot
2263:
Doran, E. I.; Crowther, P. A.; de Koter, A.; Evans, C. J.; McEvoy, C.; Walborn, N. R.; Bastian, N.; Bestenlehner, J. M.; Gräfener, G.; Herrero, A.; Kohler, K.; Maiz
Apellaniz, J.; Najarro, F.; Puls, J.; Sana, H.; Schneider, F. R. N.; Taylor, W. D.; van Loon, J. Th.; Vink, J. S. (2013). "The
178:
in astronomy is generally used to refer to an object's apparent brightness: that is, how bright an object appears to an observer. Apparent brightness depends on both the luminosity of the object and the distance between the object and observer, and also on any
1688:
988:
centered on the point would have its entire interior surface illuminated. As the radius increases, the surface area will also increase, and the constant luminosity has more surface area to illuminate, leading to a decrease in observed brightness.
1438:
1278:
657:
1324:, it is often possible to assign a certain luminosity class to a star without knowing its distance. Thus a fair measure of its absolute magnitude can be determined without knowing its distance nor the interstellar extinction.
1781:
516:
W transmitter at a distance of 1 million metres, radiating over a bandwidth of 1 MHz. By the time that power has reached the observer, the power is spread over the surface of a sphere with area
2223:
1574:
1173:
1357:
741:
312:
and its distance from Earth. Both can be measured with great accuracy in certain cases, with cool supergiants often having large angular diameters, and some cool evolved stars having
435:). Red supergiants are the largest type of star, but the most luminous are much smaller and hotter, with temperatures up to 50,000 K and more and luminosities of several million
1209:
1025:
323:
An alternative way to measure stellar luminosity is to measure the star's apparent brightness and distance. A third component needed to derive the luminosity is the degree of
926:
1499:
1470:
553:
1557:
1528:
1121:
2169:
265:
luminosity. These are not generally luminosities in the strict sense of an absolute measure of radiated power, but absolute magnitudes defined for a given filter in a
1317:). In addition to this brightness decrease from increased distance, there is an extra decrease of brightness due to extinction from intervening interstellar dust.
2378:
1193:
1070:
1048:
982:
234:, which carry off some energy (about 2% in the case of the Sun), contributing to the star's total luminosity. The IAU has defined a nominal solar luminosity of
1709:
and the luminosity in watts can be calculated from an absolute magnitude (although absolute magnitudes are often not measured relative to an absolute flux):
359:
luminous stars have much shorter lifetimes. The most luminous stars are always young stars, no more than a few million years for the most extreme. In the
187:
is a logarithmic measure of apparent brightness. The distance determined by luminosity measures can be somewhat ambiguous, and is thus sometimes called the
1293:
Luminosity is an intrinsic measurable property of a star independent of distance. The concept of magnitude, on the other hand, incorporates distance. The
363:, the x-axis represents temperature or spectral type while the y-axis represents luminosity or magnitude. The vast majority of stars are found along the
1301:. The Pogson logarithmic scale is used to measure both apparent and absolute magnitudes, the latter corresponding to the brightness of a star or other
538:
must be made for the spectral index α of the source, and a relativistic correction must be made for the fact that the frequency scale in the emitted
1967:
Schou, J.; Stewart, S. G. (2015). "IAU 2015 Resolution B3 on
Recommended Nominal Conversion Constants for Selected Solar and Planetary Properties".
1712:
2100:
227:
2490:
2206:
2173:
1920:
1893:
2317:
Singal, J.; Petrosian, V.; Lawrence, A.; Stawarz, Ł. (20 December 2011). "On the Radio and
Optical Luminosity Evolution of Quasars".
849:
1126:
2130:
Delfosse, Xavier; et al. (December 2000), "Accurate masses of very low mass stars. IV. Improved mass-luminosity relations",
367:
with blue Class O stars found at the top left of the chart while red Class M stars fall to the bottom right. Certain stars like
2516:
1335:
measure, is a logarithmic scale of observed visible brightness. The apparent magnitude is the observed visible brightness from
360:
1885:
379:
Blue and white supergiants are high luminosity stars somewhat cooler than the most luminous main sequence stars. A star like
308:, but in most cases neither can be measured directly. To determine a star's radius, two other metrics are needed: the star's
2606:
831:
943:
2445:
494:
2528:
2177:
1203:
2611:
1944:
1339:
which depends on the distance of the object. The absolute magnitude is the apparent magnitude at a distance of 10
994:
1806:
1801:
889:
827:
31:
2482:
886:
gives the value for luminosity for a black body, an idealized object which is perfectly opaque and non-reflecting:
390:, a spectral type of A2, and an effective temperature around 8,500 K, meaning it has a radius around 203
820:
486:
347:
87:
879:
711:
1354:
The difference in bolometric magnitude between two objects is related to their luminosity ratio according to:
778:. This is sometimes expressed in terms of the total (i.e. integrated over all wavelengths) luminosity of the
1796:
1988:
Nieva, M.-F (2013). "Temperature, gravity, and bolometric correction scales for non-supergiant OB stars".
1683:{\displaystyle M_{\mathrm {bol} }=-2.5\log _{10}{\frac {L_{*}}{L_{0}}}\approx -2.5\log _{10}L_{*}+71.1974}
1321:
355:
343:
324:
270:
180:
2264:
VLT-FLAMES Tarantula Survey - XI. A census of the hot luminous stars and their feedback in 30 Doradus".
2108:
1791:
290:
278:
251:
145:
418:, a spectral type of M2, and a temperature around 3,500 K, meaning its radius is about 1,000
332:
199:
When not qualified, the term "luminosity" means bolometric luminosity, which is measured either in the
1351:), therefore the bolometric absolute magnitude is a logarithmic measure of the bolometric luminosity.
2336:
2283:
2238:
2149:
2064:
2007:
1477:
1448:
1328:
remember how to convert between them, although officially, zero point values are defined by the IAU.
1288:
2401:
2590:
759:
693:
328:
313:
188:
115:
1535:
1506:
1433:{\displaystyle M_{\text{bol1}}-M_{\text{bol2}}=-2.5\log _{10}{\frac {L_{\text{1}}}{L_{\text{2}}}}}
1087:
2578:
2566:
2352:
2326:
2299:
2273:
2139:
2082:
2054:
2023:
1997:
1968:
1298:
1294:
336:
266:
184:
160:
149:
2506:
2486:
2202:
1916:
1910:
1889:
262:
2474:
1940:
242:
to promote publication of consistent and comparable values in units of the solar luminosity.
2542:
2344:
2291:
2287:
2153:
2072:
2015:
2011:
1811:
1563:
The zero point of the absolute magnitude scale is actually defined as a fixed luminosity of
1273:{\displaystyle {\frac {L}{L_{\odot }}}\approx {\left({\frac {M}{M_{\odot }}}\right)}^{3.5}.}
309:
208:
134:
59:
2043:"Bolometric correction and spectral energy distribution of cool stars in Galactic clusters"
2520:
2198:
1936:
247:
346:, stars are grouped according to temperature, with the massive, very young and energetic
2340:
2242:
2068:
652:{\displaystyle L_{\nu }={\frac {S_{\mathrm {obs} }4\pi {D_{L}}^{2}}{(1+z)^{1+\alpha }}}}
327:
that is present, a condition that usually arises because of gas and dust present in the
1302:
1297:
is a measure of the diminishing flux of light as a result of distance according to the
1178:
1055:
1033:
967:
744:
705:
223:
39:
2348:
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observed only in the infrared. Bolometric luminosities can also be calculated using a
2600:
2303:
2086:
2077:
2042:
2027:
1199:
364:
91:
2356:
743:, and in radio astronomy, assuming thermal emission the spectral index is typically
2554:
2511:
2479:
Introduction to
Stellar Astrophysics: Volume 1, Basic Stellar Observations and Data
2370:
1073:
755:
678:
535:
498:
461:
419:
391:
274:
2295:
2019:
1571:. Therefore, the absolute magnitude can be calculated from a luminosity in watts:
862:
2192:
870:
is radiating light equally in all directions. The amount passing through an area
289:
A star's luminosity can be determined from two stellar characteristics: size and
159:) of an object is a logarithmic measure of its total energy emission rate, while
2423:
1830:
809:
273:
system are defined against photometric standard stars, while others such as the
1855:
883:
543:
539:
408:
372:
164:
453:
has a temperature over 46,000 K and a luminosity of more than 6,100,000
547:
219:
95:
69:. A star with four times the radiative power of the Sun has a luminosity of
17:
133:. In astronomy, values for luminosity are often given in the terms of the
2144:
1332:
762:
for a redshift of 1 to be 6701 Mpc = 2×10 m giving a radio luminosity of
751:
269:. Several different photometric systems exist. Some such as the UBV or
258:
231:
168:
2041:
Buzzoni, A; Patelli, L; Bellazzini, M; Pecci, F. Fusi; Oliva, E (2010).
834: in this section. Unsourced material may be challenged and removed.
1856:"* Luminosity (Astronomy) - Definition, meaning - Online Encyclopedia"
1340:
1306:
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502:
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126:
111:
99:
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in their atmospheres that can be used to measure the parallax using
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1973:
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2002:
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1336:
1314:
861:
474:
432:
404:
380:
368:
38:
1305:
as seen if it would be located at an interstellar distance of 10
27:
Measurement of radiant electromagnetic power emitted by an object
317:
204:
163:
is a logarithmic measure of the luminosity within some specific
130:
107:
103:
54:
803:
779:
44:
1776:{\displaystyle L_{*}=L_{0}\times 10^{-0.4M_{\mathrm {bol} }}}
750:
For example, consider a 1 Jy signal from a radio source at a
144:. Luminosity can also be given in terms of the astronomical
257:
The term luminosity is also used in relation to particular
200:
122:
2101:"ASTR 5610, Majewski [SPRING 2016]. Lecture Notes"
1320:
By measuring the width of certain absorption lines in the
534:
More generally, for sources at cosmological distances, a
546:. So the full expression for radio luminosity, assuming
293:. The former is typically represented in terms of solar
2375:
The NIST Reference on
Constants, Units, and Uncertainty
1195:
is the distance from the observer to the light source.
874:
varies with the distance of the surface from the light.
2526:
2517:
1715:
1577:
1538:
1509:
1480:
1451:
1360:
1212:
1181:
1129:
1090:
1058:
1036:
997:
970:
892:
714:
556:
497:
over which it is measured. The observed strength, or
350:
stars boasting temperatures in excess of 30,000
98:, luminosity is the total amount of electromagnetic
2231:
1775:
1682:
1551:
1522:
1493:
1464:
1432:
1272:
1187:
1167:
1123:, so for stars and other point sources of light:
1115:
1064:
1042:
1019:
984:that radiates equally in all directions. A hollow
976:
920:
735:
651:
230:and measurement of heating. A star also radiates
90:(light) per unit time, and is synonymous with the
2047:Monthly Notices of the Royal Astronomical Society
1501:is the bolometric magnitude of the second object.
183:of light along the path from object to observer.
2404:. Institute for Astronomy - University of Hawaii
2164:
2162:
1472:is the bolometric magnitude of the first object
383:, for example, has a luminosity around 200,000
2371:"2022 CODATA Value: Stefan–Boltzmann constant"
964:Imagine a point source of light of luminosity
442:, meaning their radii are just a few tens of
8:
1559:is the second object's bolometric luminosity
1168:{\displaystyle F={\frac {L}{4\pi r^{2}}}\,,}
58:. In astronomy, this amount is equal to one
1530:is the first object's bolometric luminosity
376:and they are called giants or supergiants.
2475:"Chapter 6. The luminosities of the stars"
254:to a luminosity in a particular passband.
2330:
2277:
2143:
2076:
2058:
2001:
1972:
1758:
1757:
1746:
1733:
1720:
1714:
1668:
1655:
1634:
1624:
1618:
1609:
1583:
1582:
1576:
1543:
1537:
1514:
1508:
1485:
1479:
1456:
1450:
1422:
1412:
1406:
1397:
1378:
1365:
1359:
1261:
1248:
1239:
1234:
1222:
1213:
1211:
1180:
1161:
1152:
1136:
1128:
1107:
1089:
1080:The surface area of a sphere with radius
1057:
1035:
1004:
996:
969:
909:
891:
850:Learn how and when to remove this message
736:{\displaystyle I\propto {\nu }^{\alpha }}
727:
722:
713:
634:
610:
603:
598:
578:
577:
570:
561:
555:
542:is different from that in the observer's
354:while the less massive, typically older
2533:
1912:Introduction to Astronomy and Cosmology
1822:
1050:is the area of the illuminated surface.
460:(mostly in the UV), it is only 39
94:emitted by a light-emitting object. In
1882:Glossary of Astronomy and Astrophysics
754:of 1, at a frequency of 1.4 GHz.
407:). For comparison, the red supergiant
2400:Joshua E. Barnes (18 February 2003).
2174:Australia Telescope National Facility
304:, while the latter is represented in
7:
936:is the temperature (in kelvins) and
832:adding citations to reliable sources
529:10 / 10 / (1.26×10) W m Hz = 8×10 Jy
774:the case above, the total power is
501:, of a radio source is measured in
86:is an absolute measure of radiated
2426:. Astronomy Notes. 2 November 2010
1765:
1762:
1759:
1590:
1587:
1584:
585:
582:
579:
222:is the instrument used to measure
25:
2512:Ned Wright's cosmology calculator
1020:{\displaystyle F={\frac {L}{A}},}
756:Ned Wright's cosmology calculator
125:units, luminosity is measured in
2584:
2572:
2560:
2548:
2536:
2078:10.1111/j.1365-2966.2009.16223.x
921:{\displaystyle L=\sigma AT^{4},}
808:
411:has a luminosity around 100,000
2222:Ledrew, Glenn (February 2001).
1886:The University of Chicago Press
1494:{\displaystyle M_{\text{bol2}}}
1465:{\displaystyle M_{\text{bol1}}}
819:needs additional citations for
493:, to avoid having to specify a
261:such as a visual luminosity of
47:has an intrinsic luminosity of
2176:. 12 July 2004. Archived from
631:
618:
1:
1699:is the zero point luminosity
150:absolute bolometric magnitude
2473:Böhm-Vitense, Erika (1989).
2266:Astronomy & Astrophysics
1990:Astronomy & Astrophysics
1945:Institute for Advanced Study
1552:{\displaystyle L_{\text{2}}}
1523:{\displaystyle L_{\text{1}}}
1116:{\displaystyle A=4\pi r^{2}}
768:(2×10) / (1 + 1) = 6×10 W Hz
62:, represented by the symbol
2349:10.1088/0004-637X/743/2/104
2296:10.1051/0004-6361/201321824
2020:10.1051/0004-6361/201219677
1941:"Solar Neutrino Viewgraphs"
1807:Orders of magnitude (power)
1802:List of most luminous stars
1331:The magnitude of a star, a
1076:of the illuminated surface.
361:Hertzsprung–Russell diagram
32:Luminosity (disambiguation)
2628:
2523: (archived 8 May 2015)
2483:Cambridge University Press
2132:Astronomy and Astrophysics
1286:
786:, giving a radio power of
512:For example, consider a 10
277:are defined in terms of a
29:
2319:The Astrophysical Journal
2191:Karttunen, Hannu (2003).
1947:School of Natural Science
1283:Relationship to magnitude
944:Stefan–Boltzmann constant
527:, so its flux density is
342:In the current system of
2402:"The Inverse-Square Law"
2105:www.faculty.virginia.edu
1880:Hopkins, Jeanne (1980).
1831:"Luminosity | astronomy"
1206:approximately as below:
776:4×10 × 1.4×10 = 5.7×10 W
2288:2013A&A...558A.134D
2154:2000A&A...364..217D
2012:2013A&A...550A..26N
1835:Encyclopedia Britannica
1797:List of brightest stars
325:interstellar extinction
1915:. Wiley. p. 193.
1777:
1684:
1553:
1524:
1495:
1466:
1434:
1274:
1189:
1169:
1117:
1066:
1044:
1021:
978:
922:
882:equation applied to a
875:
737:
653:
344:stellar classification
174:In contrast, the term
88:electromagnetic energy
80:
2607:Astrophysics concepts
2507:Luminosity calculator
2224:"The Real Starry Sky"
2194:Fundamental Astronomy
2170:"Luminosity of Stars"
1909:Morison, Ian (2013).
1792:Glossary of astronomy
1778:
1685:
1554:
1525:
1496:
1467:
1435:
1275:
1202:, luminosity is also
1190:
1170:
1118:
1067:
1045:
1022:
979:
932:is the surface area,
923:
865:
738:
666:is the luminosity in
654:
291:effective temperature
279:spectral flux density
252:bolometric correction
135:luminosity of the Sun
42:
2446:"Absolute Magnitude"
1713:
1575:
1536:
1507:
1478:
1449:
1358:
1289:Bolometric magnitude
1210:
1179:
1127:
1088:
1056:
1034:
995:
968:
890:
828:improve this article
712:
554:
485:The luminosity of a
337:circumstellar matter
226:over a wide band by
116:astronomical objects
102:emitted per unit of
30:For other uses, see
2612:Physical quantities
2450:csep10.phys.utk.edu
2341:2011ApJ...743..104S
2243:2001JRASC..95...32L
2069:2010MNRAS.403.1592B
800:Luminosity formulae
760:luminosity distance
694:luminosity distance
329:interstellar medium
189:luminosity distance
2485:. pp. 41–48.
2424:"Magnitude System"
1773:
1680:
1549:
1520:
1491:
1462:
1430:
1299:inverse-square law
1295:apparent magnitude
1270:
1185:
1165:
1113:
1062:
1040:
1017:
974:
946:, with a value of
918:
876:
733:
649:
333:Earth's atmosphere
285:Stellar luminosity
267:photometric system
209:solar luminosities
185:Apparent magnitude
161:absolute magnitude
81:
2492:978-0-521-34869-0
2208:978-3-540-00179-9
2180:on 9 August 2014.
1922:978-1-118-68152-7
1895:978-0-226-35171-1
1640:
1546:
1517:
1488:
1459:
1428:
1425:
1415:
1381:
1368:
1254:
1228:
1198:For stars on the
1188:{\displaystyle r}
1159:
1065:{\displaystyle F}
1043:{\displaystyle A}
1012:
977:{\displaystyle L}
860:
859:
852:
700:is the redshift,
647:
207:, or in terms of
16:(Redirected from
2619:
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2414:
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2147:
2145:astro-ph/0010586
2127:
2121:
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2118:
2116:
2111:on 24 April 2021
2107:. Archived from
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2005:
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1906:
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1899:
1884:(2nd ed.).
1877:
1871:
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1852:
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1841:
1827:
1812:Solar luminosity
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1413:
1407:
1402:
1401:
1383:
1382:
1379:
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1366:
1346:
1322:stellar spectrum
1312:
1279:
1277:
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1271:
1266:
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1120:
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975:
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951:
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919:
914:
913:
880:Stefan–Boltzmann
855:
848:
844:
841:
835:
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804:
795:
785:
777:
769:
767:
742:
740:
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677:is the observed
669:
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607:
590:
589:
588:
571:
566:
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530:
526:
522:
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508:
507:1 Jy = 10 W m Hz
492:
481:Radio luminosity
472:
449:. For example,
430:
402:
310:angular diameter
241:
239:
78:
60:solar luminosity
57:
52:
21:
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2521:Wayback Machine
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2469:
2467:Further reading
2464:
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2201:. p. 289.
2199:Springer-Verlag
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1207:
1204:related to mass
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1103:
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397:
389:
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287:
248:Wolf-Rayet star
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129:per second, or
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35:
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2501:External links
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1303:celestial body
1287:Main article:
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708:(in the sense
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2037:
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2017:
2013:
2009:
2004:
1999:
1995:
1991:
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1981:
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1970:
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1959:
1946:
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1937:Bahcall, John
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1200:main sequence
1196:
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1108:
1104:
1100:
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959:10 W⋅m⋅K
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885:
881:
873:
869:
866:Point source
864:
854:
851:
843:
833:
829:
823:
822:
817:This section
815:
811:
806:
805:
799:
797:
791:
781:
771:
761:
758:calculates a
757:
753:
748:
746:
728:
723:
718:
715:
707:
703:
699:
695:
691:
680:
673:
662:
641:
638:
635:
627:
624:
621:
611:
604:
600:
594:
591:
574:
567:
562:
558:
550:emission, is
549:
545:
541:
537:
532:
521:
510:
504:
500:
496:
488:
480:
478:
476:
468:
464:
456:
452:
445:
438:
434:
426:
422:
414:
410:
406:
398:
394:
386:
382:
377:
374:
370:
366:
365:main sequence
362:
357:
353:
349:
345:
340:
338:
334:
330:
326:
321:
319:
315:
311:
307:
300:
296:
292:
284:
282:
280:
276:
272:
268:
264:
260:
255:
253:
249:
243:
233:
229:
225:
221:
210:
206:
202:
194:
192:
190:
186:
182:
177:
172:
170:
166:
162:
155:
151:
147:
140:
136:
132:
128:
124:
119:
117:
113:
109:
105:
101:
97:
93:
92:radiant power
89:
85:
74:
65:
61:
56:
46:
41:
37:
33:
19:
2591:Solar System
2478:
2453:. Retrieved
2449:
2440:
2428:. Retrieved
2418:
2408:26 September
2406:. Retrieved
2395:
2383:. Retrieved
2374:
2365:
2322:
2318:
2312:
2269:
2265:
2258:
2246:. Retrieved
2234:
2230:
2217:
2193:
2186:
2178:the original
2135:
2131:
2125:
2113:. Retrieved
2109:the original
2104:
2095:
2050:
2046:
2036:
1993:
1989:
1983:
1961:
1949:. Retrieved
1931:
1911:
1904:
1881:
1875:
1863:. Retrieved
1859:
1850:
1838:. Retrieved
1834:
1825:
1708:
1692:
1562:
1441:
1353:
1330:
1326:
1319:
1292:
1197:
1081:
1079:
1074:flux density
991:
963:
938:
933:
929:
877:
871:
867:
846:
837:
826:Please help
821:verification
818:
789:
772:
749:
701:
697:
686:
679:flux density
671:
660:
536:k-correction
533:
519:
511:
499:flux density
487:radio source
484:
462:
454:
443:
436:
420:
412:
392:
384:
378:
341:
322:
298:
288:
256:
244:
198:
175:
173:
153:
148:system: the
138:
120:
83:
82:
72:
63:
36:
18:Luminosities
2579:Outer space
2567:Spaceflight
2279:1308.3412v1
2138:: 217–224,
2053:(3): 1592.
745:equal to 2.
696:in metres,
331:(ISM), the
195:Measurement
169:filter band
114:, or other
2601:Categories
2455:2 February
2381:. May 2024
2325:(2): 104.
2115:3 February
1974:1510.07674
1860:en.mimi.hu
1818:References
884:black body
544:rest frame
540:rest frame
409:Betelgeuse
373:Betelgeuse
228:absorption
181:absorption
176:brightness
165:wavelength
84:Luminosity
2543:Astronomy
2332:1101.2930
2304:118510909
2237:: 32–33.
2087:119181086
2060:1002.1972
2028:119275940
2003:1212.0928
1748:−
1740:×
1722:∗
1705:10 W
1670:∗
1662:
1646:−
1643:≈
1626:∗
1616:
1600:−
1569:10 W
1404:
1388:−
1372:−
1250:⊙
1231:≈
1224:⊙
1146:π
1101:π
900:σ
840:July 2023
784:3.86×10 W
782:which is
729:α
724:ν
719:∝
642:α
595:π
563:ν
548:isotropic
525:1.26×10 m
523:or about
495:bandwidth
275:AB system
259:passbands
240:10 W
232:neutrinos
220:bolometer
167:range or
146:magnitude
96:astronomy
2357:10579880
2272:: A134.
1786:See also
1347:10
1333:unitless
752:redshift
473:10
431:10
403:10
216:☉
53:10
2529:Portals
2519:at the
2337:Bibcode
2284:Bibcode
2239:Bibcode
2150:Bibcode
2065:Bibcode
2008:Bibcode
1996:: A26.
1865:24 June
1840:24 June
1678:71.1974
1442:where:
1307:parsecs
1072:is the
942:is the
788:1.5×10
704:is the
692:is the
505:where
356:Class M
348:Class O
306:kelvins
271:Johnson
203:units,
71:4
2489:
2430:2 July
2385:18 May
2355:
2302:
2248:2 July
2205:
2085:
2026:
1951:3 July
1919:
1892:
1701:3.0128
1690:where
1565:3.0128
1315:metres
1175:where
1027:where
986:sphere
928:where
764:10 × 4
702:α
683:W m Hz
659:where
514:
503:Jansky
451:R136a1
335:, and
314:masers
263:K-band
218:). A
127:joules
112:galaxy
100:energy
2555:Stars
2353:S2CID
2327:arXiv
2300:S2CID
2274:arXiv
2227:(PDF)
2140:arXiv
2083:S2CID
2055:arXiv
2024:S2CID
1998:arXiv
1969:arXiv
1337:Earth
948:5.670
399:(1.41
381:Deneb
369:Deneb
295:radii
236:3.828
205:watts
131:watts
106:by a
55:watts
2487:ISBN
2457:2019
2432:2012
2410:2012
2387:2024
2379:NIST
2250:2012
2203:ISBN
2117:2019
1953:2012
1917:ISBN
1890:ISBN
1867:2018
1842:2018
1487:bol2
1458:bol1
1380:bol2
1367:bol1
1343:(3.1
1309:(3.1
878:The
668:W Hz
491:W Hz
469:(2.7
427:(7.0
371:and
318:VLBI
108:star
104:time
49:3.83
43:The
2345:doi
2323:743
2292:doi
2270:558
2136:364
2073:doi
2051:403
2016:doi
1994:550
1751:0.4
1653:log
1649:2.5
1607:log
1603:2.5
1395:log
1391:2.5
1313:10
1263:3.5
1084:is
955:...
953:419
950:374
830:by
780:Sun
681:in
675:obs
477:).
157:bol
121:In
45:Sun
2603::
2481:.
2477:.
2448:.
2377:.
2373:.
2351:.
2343:.
2335:.
2321:.
2298:.
2290:.
2282:.
2268:.
2235:95
2233:.
2229:.
2197:.
2172:.
2161:^
2148:,
2134:,
2103:.
2081:.
2071:.
2063:.
2049:.
2045:.
2022:.
2014:.
2006:.
1992:.
1943:.
1939:.
1888:.
1858:.
1833:.
1744:10
1657:10
1611:10
1399:10
1341:pc
961:.
796:.
770:.
747:)
685:,
670:,
531:.
520:πr
509:.
297:,
281:.
201:SI
191:.
171:.
137:,
123:SI
118:.
110:,
2531::
2495:.
2459:.
2434:.
2412:.
2389:.
2359:.
2347::
2339::
2329::
2306:.
2294::
2286::
2276::
2252:.
2241::
2211:.
2152::
2142::
2119:.
2089:.
2075::
2067::
2057::
2030:.
2018::
2010::
2000::
1977:.
1971::
1955:.
1925:.
1898:.
1869:.
1844:.
1766:l
1763:o
1760:b
1755:M
1735:0
1731:L
1727:=
1718:L
1703:×
1696:0
1693:L
1675:+
1666:L
1636:0
1632:L
1622:L
1597:=
1591:l
1588:o
1585:b
1580:M
1567:×
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1516:1
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1483:M
1454:M
1424:2
1420:L
1414:1
1410:L
1385:=
1376:M
1363:M
1349:m
1345:×
1311:×
1268:.
1257:)
1246:M
1242:M
1237:(
1220:L
1216:L
1183:r
1163:,
1154:2
1150:r
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1139:L
1134:=
1131:F
1109:2
1105:r
1098:4
1095:=
1092:A
1082:r
1060:F
1038:A
1015:,
1010:A
1007:L
1002:=
999:F
972:L
957:×
939:σ
934:T
930:A
916:,
911:4
907:T
903:A
897:=
894:L
872:A
868:S
853:)
847:(
842:)
838:(
824:.
793:⊙
790:L
766:π
716:I
698:z
689:L
687:D
672:S
664:ν
661:L
639:+
636:1
632:)
628:z
625:+
622:1
619:(
612:2
605:L
601:D
592:4
586:s
583:b
580:o
575:S
568:=
559:L
518:4
475:m
471:×
466:☉
463:R
458:⊙
455:L
447:⊙
444:R
440:⊙
437:L
433:m
429:×
424:☉
421:R
416:⊙
413:L
405:m
401:×
396:☉
393:R
388:⊙
385:L
352:K
302:⊙
299:R
238:×
213:L
211:(
154:M
152:(
142:⊙
139:L
79:.
76:⊙
73:L
67:⊙
64:L
51:×
34:.
20:)
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