108:, which was located by the SEDs it produced and then optically verified. It and other white storm clouds were found to be brighter in conjunction with higher rates of SEDs. The Dragon Storm can range over 2,000 miles and is located at a planetocentric latitude of 35° south. This planet region is called "storm alley" as all storm activity on Saturn was concentrated here in a 1.5° band from 2002 to 2010. SED storms switched from the southern hemisphere "storm alley" before the
97:
136:
radio telescope, and the data was combined with real-time information from
Cassini. These efforts were made easier by the high intensity of the SEDs occurring during the month-long SED storm E. The process was repeated in November 2007 during the eight-month-long storm F and produced a high degree of
83:
in
November 1980. The term was subsequently coined by Warwick et al. in April 1981 in the Journal Planetary Radio Astronomy Observations from Voyager 1 Near Saturn. It was initially uncertain whether these SEDs were associated with storms in the planet's atmosphere or if they were originating in its
119:
During the
Cassini mission, it was also discovered that SEDs could be detected over the horizon. This phenomenon, known as over-the-horizon events, was made possible by the previously mentioned combination of radio and optical observations. It is theorized that this occurs when SED radio waves are
50:
The charging of particles in thunderstorms on earth is most effective at 248 to 263 K. On Saturn this is at 8-10 bars or 200 km below the cloud tops. Both lighting on earth and SEDs probably have a similar charging mechanism in
439:
Zakharenko, V.; Mylostna, C.; Konovalenko, A.; Zarka, P.; Fischer, G.; Grießmeier, J. -M.; Litvinenko, G.; Rucker, H.; Sidorchuk, M.; Ryabov, B.; Vavriv, D.; Ryabov, V.; Cecconi, B.; Coffre, A.; Denis, L. (2012-02-01).
88:, which was also the proposed reason for a narrow feature also found. This was disputed in 1983 by Kaiser et al., who argued that the occultation caused by the planet lasted too long for SEDs to originate in the rings.
47:'s Voyager 1 mission, the scientific community has gained further understanding through the following Voyager 2 and Cassini missions in conjunction with ground-based observation and data gathering methods.
225:
Warwick, J. W.; Pearce, J. B.; Evans, D. R.; Carr, T. D.; Schauble, J. J.; Alexander, J. K.; Kaiser, M. L.; Desch, M. D.; Pedersen, M.; Lecacheux, A.; Daigne, G.; Boischot, A.; Barrow, C. H. (1981-04-10).
140:
At this same time as storm E, amateur astronomers became engaged in observing Saturn's storms. Storm E, observed by
Cassini, was the first long-lasting SED storm while Saturn was distant from
361:
Dyudina, Ulyana A.; Ingersoll, Andrew P.; Ewald, Shawn P.; Porco, Carolyn C.; Fischer, Georg; Kurth, William; Desch, Michael; Del Genio, Anthony; Barbara, John; Ferrier, Joseph (2007-10-01).
133:
485:
144:, making it high in the sky for ground-based observers. In the images captured by amateurs, the SED storms proved easily detectable, manifesting as bright white spots.
67:
on Saturn. Thunderstorms can last days or even months on Saturn, but storms can also be absent for years. One SED illuminates a cloud region about 200 km in diameter.
104:
When the
Cassini mission reached Saturn in 2004, SEDs and optical storm observations were finally directly linked. This occurred when Cassini ISS imaged the
43:(VLF) radio band, between 3 Hz and 30 kHz. This makes SED signals at least 10,000 times stronger. While first discovered by
164:
Fischer, G.; Dyudina, U. A.; Kurth, W. S.; Gurnett, D. A.; Zarka, P.; Barry, T.; Delcroix, M.; Go, C.; Peach, D. (2011-11-21),
116:
of 2010 in the northern hemisphere. The 2010 great white spot is associated with a higher flash rate of 10 SEDs per second.
193:
Sánchez-Lavega, Agustín; Fischer, Georg; Li, Cheng; García-Melendo, Enrique; del Río-Gaztelurrutia, Teresa (2024-01-24),
448:. Surfaces, atmospheres and magnetospheres of the outer planets and their satellites and ring systems: Part VII.
105:
132:
in
January/February 2006. At this time, SED storm E lasted approximately one month. The ground team used the
402:"Polarization measurements of Saturn Electrostatic Discharges with Cassini/RPWS below a frequency of 2 MHz"
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Evans, D. R.; Romig, J. H.; Hord, C. W.; Simmons, K. E.; Warwick, J. W.; Lane, A. L. (September 1982).
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Fischer, G.; Gurnett, D. A.; Lecacheux, A.; Macher, W.; Kurth, W. S. (December 2007).
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rings. Evans et al. hypothesized that they originated from a satellite located within
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363:"Lightning storms on Saturn observed by Cassini ISS and RPWS during 2004–2006"
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442:"Ground-based and spacecraft observations of lightning activity on Saturn"
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around freezing level. Flashes on Saturn have a total energy of about 10
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324:"Atmospheric storm explanation of saturnian electrostatic discharges"
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80:
24:
228:"Planetary Radio Astronomy Observations from Voyager 1 Near Saturn"
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52:
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The first reliable ground-based detections of SEDs occurred in
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Kaiser, M. L.; Connerney, J. E. P.; Desch, M. D. (May 1983).
75:
369:. Deep Impact Mission to Comet 9P/Tempel 1, Part 2.
35:(1-40 MHz). Terrestrial lighting events on
285:"The source of Saturn electrostatic discharges"
120:temporarily trapped under Saturn's ionosphere.
406:Journal of Geophysical Research: Space Physics
8:
137:coincidence between the UTR-2 and Cassini.
19:(also referred to as SEDs) are atmospheric
486:Planetary atmospheres of the Solar System
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204:
173:
166:Overview of Saturn lightning observations
100:SEDs observed by Cassini in November 2009
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23:events in convective weather storms on
7:
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186:
184:
159:
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14:
196:Moist Convective Storms on Saturn
63:. Strokes typically last for 100
17:Saturn Electrostatic Discharges
39:, in comparison, occur in the
1:
379:10.1016/j.icarus.2007.03.035
244:10.1126/science.212.4491.239
446:Planetary and Space Science
507:
79:mission as it passed near
59:and typically last for 70
458:10.1016/j.pss.2011.07.021
124:Ground based observations
112:in August 2009 to the
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418:10.1029/2007JA012592
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41:very low frequency
295:(5880): 236–237.
238:(4491): 239–243.
142:solar conjunction
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340:10.1038/303050a0
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301:10.1038/299236a0
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253:2060/19820006164
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114:great white spot
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334:(5912): 50–53.
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86:Saturn's B Ring
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33:radio emissions
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373:(2): 545–555.
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29:high frequency
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27:that produce
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452:(1): 53–59.
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210:, retrieved
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106:Dragon Storm
103:
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65:microseconds
61:milliseconds
53:water clouds
49:
16:
15:
480:Categories
212:2024-05-08
206:2401.13294
148:References
466:0032-0633
426:0148-0227
387:0019-1035
348:1476-4687
309:1476-4687
262:0036-8075
175:1111.4919
77:Voyager 1
21:lightning
270:17783837
412:(A12).
232:Science
130:Ukraine
110:equinox
92:Cassini
71:Voyager
491:Saturn
464:
424:
385:
367:Icarus
346:
328:Nature
307:
289:Nature
268:
260:
81:Saturn
57:Joules
25:Saturn
201:arXiv
170:arXiv
134:UTR-2
37:Earth
31:(HF)
462:ISSN
422:ISSN
383:ISSN
344:ISSN
305:ISSN
266:PMID
258:ISSN
45:NASA
454:doi
414:doi
410:112
375:doi
371:190
336:doi
332:303
297:doi
293:299
248:hdl
240:doi
236:212
482::
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450:61
444:.
420:.
408:.
404:.
381:.
365:.
342:.
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303:.
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230:.
199:,
183:^
168:,
156:^
468:.
456::
428:.
416::
389:.
377::
350:.
338::
311:.
299::
272:.
250::
242::
203::
172::
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