Aurora on Mars
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Auroras have been found on Mars but they are very different from the high-altitude auroras found on Earth. They are occur in the upper atmosphere of Mars and are diffuse and often localized.[1] Ever since their discovery, it has been an area of active research. Mars lacks a substantial magnetic field (see: magnetic field of Mars) due to its small size and faster cooling, instead its crustal magnetic field (parts of the Martian magnetic field trapped in the planets crust) is distributed throughout the planet. Its interaction with the surrounding plasma environment (specifically with electrons and protons) leads to a number of complex processes. This results in several types of auroras that are uncommon here on Earth.[2]
Auroras found on Mars occur in the upper atmosphere during the night and are very diffuse. They are mostly found having ultraviolet emissions although some visable emission auroras do occur.[3][4]
History of Observation
[edit]On 11 August 2004,[5] the European Space Agency's Mars Express found an ultraviolet glow coming from "magnetic umbrellas" in the Southern Hemisphere.[6] Mars does not have a global magnetic field which guides charged particles entering the atmosphere. Mars has multiple umbrella-shaped magnetic fields mainly in the Southern Hemisphere, which are remnants of a global field that decayed billions of years ago.[7]
In late December 2014, NASA's MAVEN spacecraft detected evidence of widespread auroras in Mars' northern hemisphere, from about 20°–30°N latitude. The particles causing the aurora penetrated into the Martian atmosphere, creating auroras below 100 km above the surface, Earth's auroras range from 100 km to 500 km above the surface. Magnetic fields in the solar wind drape over Mars, into the atmosphere, and the charged particles follow the solar wind magnetic field lines into the atmosphere, causing auroras to occur outside the magnetic umbrellas.[8]
On 18 March 2015, NASA reported the detection of an aurora that is not fully understood and an unexplained dust cloud in the Martian atmosphere.[9]
In September 2017, NASA reported that radiation levels on the Martian surface were temporarily doubled, and were associated with an aurora 25 times brighter than any observed earlier, due to a massive, unexpected solar storm in the middle of the month.[10]
In March 2022, a possible explanation of the auroras observed on Mars was reported.[11] In 2025, the Perseverance rover had detected a green visable-wavelength aurora on Mars.[12]
References
[edit]- ^ Johnston, B. J.; Schneider, N. M.; Jain, S. K.; Milby, Z.; Deighan, J.; Bowers, C. F.; DiBraccio, G. A.; Gérard, J.-C.; Soret, L.; Girazian, Z.; Brain, D. A.; Ruhunusiri, S.; Curry, S. (2023). "Discrete Aurora at Mars: Insights Into the Role of Magnetic Reconnection". Geophysical Research Letters. 50 (24): e2023GL104198. Bibcode:2023GeoRL..5004198J. doi:10.1029/2023GL104198. ISSN 1944-8007.
- ^ Atri, Dimitra; Dhuri, Dattaraj B.; Simoni, Mathilde; Sreenivasan, Katepalli R. (2022). "Auroras on mars: From discovery to new developments". European Physical Journal D. 76 (12): 235. arXiv:2209.15229. Bibcode:2022EPJD...76..235A. doi:10.1140/epjd/s10053-022-00566-5.
- ^ Okiyama, Taishin; Seki, Kanako; Nakamura, Yuki; Lillis, Robert J.; Rahmati, Ali; Larson, Davin E.; DiBraccio, Gina A.; Schneider, Nicholas M.; Jain, Sonal K.; Sakata, Ryoya; Curry, Shannon (2025). "Study of Variation Mechanisms of the Martian Diffuse Aurora Based on Monte Carlo Simulations and MAVEN Observations". Journal of Geophysical Research: Space Physics. 130 (2): e2024JA033420. Bibcode:2025JGRA..13033420O. doi:10.1029/2024JA033420. ISSN 2169-9402.
- ^ Knutsen, Elise W.; McConnochie, Timothy H.; Lemmon, Mark; Donaldson, Chris; Francis, Raymond; Legett, Carey; Viet, Shayla B.; Soret, Lauriane; Toledo, Daniel; Apéstigue, Victor; Witasse, Olivier; Montmessin, Franck; Jolitz, Rebecca; Schneider, Nicolas M.; Tamppari, Leslie (2025-05-16). "Detection of visible-wavelength aurora on Mars". Science Advances. 11 (20): eads1563. doi:10.1126/sciadv.ads1563. PMC 12077521. PMID 40367182.
- ^ "Mars Express discovers aurorae on Mars". www.esa.int. Retrieved 2024-09-07.
- ^ Bryant, Mike (2015-05-14). "Auroras on Mars". MAVEN. Retrieved 2024-09-07.
- ^ "In an ultraviolet glow, auroras on Mars spotted by UAE orbiter". NBC News. 8 July 2021. Retrieved 2021-12-07.
- ^ "Auroras on Mars – NASA Science". science.nasa.gov. 10 May 2015. Retrieved 12 May 2015.
This article incorporates text from this source, which is in the public domain.
- ^ Brown, Dwayne; Neal-Jones, Nancy; Steigerwald, Bill; Scott, Jim (18 March 2015). "NASA Spacecraft Detects Aurora and Mysterious Dust Cloud around Mars". NASA. Release 15-045. Retrieved 18 March 2015. This article incorporates text from this source, which is in the public domain.
- ^ Webster, Guy; Neal-Jones, Nancy; Scott, Jim; Schmid, Deb; Cantillo, Laurie; Brown, Dwayne (29 September 2017). "Large Solar Storm Sparks Global Aurora and Doubles Radiation Levels on the Martian Surface". NASA. This article incorporates text from this source, which is in the public domain.
- ^ Girazian, Z.; et al. (27 March 2022). "Space Physics: Discrete Aurora at Mars: Dependence on Upstream Solar Wind Conditions" (PDF). Journal of Geophysical Research. 127 (4): e2021JA030238. doi:10.1029/2021JA030238. PMC 9287011. PMID 35866072. S2CID 246029112.
- ^ Knutsen, Elise W.; McConnochie, Timothy H.; Lemmon, Mark; Donaldson, Chris; Francis, Raymond; Legett, Carey; Viet, Shayla B.; Soret, Lauriane; Toledo, Daniel; Apéstigue, Victor; Witasse, Olivier; Montmessin, Franck; Jolitz, Rebecca; Schneider, Nicolas M.; Tamppari, Leslie (2025-05-16). "Detection of visible-wavelength aurora on Mars". Science Advances. 11 (20): eads1563. doi:10.1126/sciadv.ads1563. PMC 12077521. PMID 40367182.