"When the astronauts go into space, what protects them from solar radiation (microwaves, etc.) which the ozone and atmosphere protect the Earth from?"
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Question
What are some of the astronomical events that make it possible for there to be life on Earth?
The most important requirements for life anywhere are liquid water and an energy source. The Sun is our main energy source through photosynthesis, and the water on Earth is liquid because we have the right combination of distance from the Sun and of atmospheric greenhouse effect to keep moderate surface temperatures. Much of our water is thought to have come from asteroid and comet bombardment early in the history of the Earth. Presumably we also need stability: a stable orbit, a star that does not vary much, and not too many lethal impacts from comets and asteroids. Beyond this short list, it is not clear which properties of the Earth are really necessary for life. Many of the other possibilities are discussed in the best-selling book "Rare Earth" by Peter Ward and Don Brownlee.
David Morrison
NAI Senior Scienetist
August 11, 2004
- How frequently are questions answered?
- I asked a question but there was no answer?
- Who is the Astrobiologist answering these questions?
- Will I get an email when my question is answered?
- What college courses should I take to become an astrobiologist?
- How can I get a job as an astrobiologist at NASA?
- Have aliens visited Earth? Are UFOs real?
- Is there a planet or brown dwarf called Nibiru or Eris that is approaching the Earth and threatening our planet with widespread destruction?
- Is it true that the Sun will be in the center of the Milky Way Galaxy in December 2012 and that this will cause a pole shift and massive destruction.
- Has NASA discovered life on other worlds?
- Astrobiology Career Path Suggestions
