Content with the tag: “asteroids”
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Asteroid Impact Could Destroy Ozone Layer
New research funded by a NASA Exobiology grant is helping scientists understand what would happen to life on Earth if an asteroid crashed into the deep ocean. The model shows that a medium-sized asteroid could affect atmospheric chemistry on our planet, resulting in global ozone depletion. Ozone in Earth’s atmosphere helps protect living organisms from ultraviolet radiation. If ozone levels were depleted for a long period of time, life could face a difficult future.Source: [Planetary Science Institute ]
October 27, 2010 / Posted by: Aaron Gronstal
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Getting WISE About Nemesis
Artist concept of the NASA WISE mission. Image: NASA/JPL
Is our Sun part of a binary star system? An unseen companion star, nicknamed “Nemesis,” may be sending comets towards Earth. Throughout history, such impacts could have had a profound effect on the evolution of the biosphere by causing regular mass extinctions. If Nemesis exists, NASA’s new WISE telescope should be able to spot it.Source: [astrobio.net]
March 11, 2010 / Written by: Leslie Mullen
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Marco Polo and Meteorites
Asteroids and comets have been a major focus of recent NASA missions. From Deep Impact to Stardust, and the current Dawn mission, astrobiologists have been examining these fascinating celestial bodies in order to understand the role they may have played in the origin of life on our planet. These rocks in space are also ancient records from a time when our solar system was being born. The wealth of scientific information that can be gleaned from asteroids has also sparked interest from space agencies outside of the United States....Source: [Astrobiology Magazine]
December 2, 2008 / Posted by: Aaron Gronstal
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lassen volcanic national park late accretion late bombardment late heavy bombardment ldn 673 left-handed lefty level of analysis lexen program life life and environment life detection life elsewhere in the universe life in extreme life in our solar system life in the solar system life in the universe life on land life on mars ligase light light environments lightning li isotopes limits of life linda billings lipids liquid liquid chromatography mass spectrometry liquid hydrocarbons lithic clasts lithium lithophiles living in the microbial world: summer teacher enhancement - august 1999 lmt low-mass low-mass stars low albedo deposits lu-hf isotopes lunar-like satellites lunar evolution lunar exploration lunar impacts lunar samples lysis mafic maghemite magma ocean magnesite magnesium magnet magnetic field magnetic fields magnetic fields - stars magnetite magnets main belt asteroids main belt comet main belt comets maine malawimonas jakobiformis maldi-mass spectrometry mantle mantle 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