110 likes | 242 Views
Presented by: Kyle Thompson and Ginny Connor. The Effect of a Strong Stellar Flare on the Atmospheric Chemistry of an Earth-like Planet Orbiting an M Dwarf. Overview. The abundance of M Dwarfs A solar flare’s impact on atmospheric ozone Two distinct tests With charged particles
E N D
Presented by: Kyle Thompson and Ginny Connor The Effect of a Strong Stellar Flare on the Atmospheric Chemistry of an Earth-like Planet Orbiting an M Dwarf
Overview • The abundance of M Dwarfs • A solar flare’s impact on atmospheric ozone • Two distinct tests • With charged particles • With uncharged (UV radiation only) particles
M Dwarfs • Abundant • Long living • 70% of all stars in our galaxy • Infrared radiation • Low luminosity stars • Closer habitable zone
The Two Tests • Charged particles vs. uncharged (UV radiation only) particles • Ionizing particles emitted during a flare may be more dangerous depending on how much of the particle flux strikes the planet
Effect on Temperature • No significant temperature change for either test • Final temperature difference was 0.1 K • Greatest difference was observed in the Mesosphere • Ozone variations cause temperature fluctuations in the upper atmosphere, but these fluctuations are small, and the climate at the surface is unaffected
Effect on Water Vapor • Depleted in the Stratosphere • 30 ppmv – 0.3 ppmv
Effect on Ozone Density • Noticeable decrease in the Stratosphere during the impulsive phase • Continued to increase until the flare ended • Much of the potentially life-damaging UV radiation goes into photolyzing ozone in the Stratosphere, which prevents it from reaching the planetary surface
Effect on Total Ozone Column Depth • UV radiation only: 1,000 seconds after the flare, depletion was only 1% • With charged photons: large effect but stabilizes after 4 months • Given that M Dwarfs can be active on timescales of days to weeks, the atmosphere may not return to equilibrium before another flare occurs
Conclusion • For an oxygen-rich, Earth-like planet in the habitable zone of an active M Dwarf, stellar flares do not necessarily affect habitability
Works Cited • Segura, Antigona, Lucianne M. Walkowicz, Victoria Meadows, James Kasting, and Suzanne Hawley. "The Effect of a Strong Stellar Flare on the Atmospheric Chemistry of an Earth-like Planet Orbiting an M Dwarf." Astrobiology 10.7 (2010): 751-71. Web.