Re: what is life chemicals

Hi Kathleen,

Nice question! I expect you know that the topic of life in space is a big one at the moment. Let's start with the moon.

We've known for a long time that the moon is airless, has no liquid water and ranges in temperature from very cold to very hot. So it doesn't seem like a likely place to find life. Still, when astronauts went to the moon they took no chances and for the first manned Apollo landings, the crew were kept in quarantine for 3 weeks when they got back. Happily, they didn't catch any moon bugs. The soil from the moon was examined for signs of life such as the presence of bacteria or organic compounds. Some amino acids (which form proteins in living things) were detected, but these are distributed throughout space. So it was concluded that there is no life on the moon. Go to Google and try typing "lunar receiving laboratory" to find out about how the moon samples were processed.

Some bacteria from the earth did survive in suspended animation on the moon, though. They travelled on an unmanned spacecraft called Surveyor III and were revived when a piece of it was brought back by the astronauts. Read all about it!.

Mars is much more interesting. In 1976, 2 craft called Viking I and Viking II were sent to Mars. They carried a very sophisticated robotic laboratory to look for signs of microbial life on Mars. You can read about the experiments on this page. They were designed to see if organic compounds were trapped by organisms in the soil. Taken together, they seemed to indicate that there was no life on Mars. However, Gilbert Levin, who designed an experiment called the labelled release experiment, thinks that life was detected on Mars. You can read about that on his website.

Of course, these experiments were all designed to look for life as we know it on Earth. There might be other kinds of life of which we have no experience-but then, we wouldn't know how to look for it! And there are good reasons to believe that all life must follow some basic rules.

If you are interested to know more about life in space, try the very good Astrobiology Web. There are lots of good links there.

Neil Saunders