The Search for Life

If there is, or has been, life on other planets, in our own solar system or around other stars:

• we may be able to observe living organisms (e.g. microorganisms), or their fossilised remains, directly, for example, by actually going to Mars or Europa (a satellite of Jupiter), by using robots to send back pictures or by using robots to collect samples to bring back to Earth;
  
  
• we may be able to detect living organisms by the chemical changes they produce in a closed system (e.g. inside a closed container or in the atmosphere of their planet); because of living organisms, the atmosphere of the Earth is very different from what it would be purely from chemical and geological processes; for example, there is much more oxygen;
  
  
• we may be able to receive signals from other species with technologies that are at least as advanced as our own. The search for extra-terrestrial intelligence (SETI), using radio telescopes to try to find meaningful signals in a narrow band of wavelengths (i.e. not just ‘noise’), has gone on for more than forty years, so far without success.

You can help out by 'donating' your spare computer power - go to SETI@Home

• Are We Alone?
• Life on Other Planets
• The History of S.E.T.I.
• Hubble - 15 Years of Discovery - 1 - The Hubble Story

ESA's search for Life

NASA's current missions - Mars Landers

Hubble Finds First Organic Molecule on an Exoplanet