Image: The next generation of space telescopes will be capable of detecting "biosignatures" in the light from planets orbiting other stars (Image: G. Bacon STSCI / ESA / NASA)From New Scientist:
SIGNS of life on planets beyond our own solar system may soon be in our sights. Experiments and calculations presented at an astrobiology meeting last week reveal how the coming generation of space telescopes will for the first time be capable of detecting "biosignatures" in the light from planets orbiting other stars.
Any clues about life on these exoplanets will have to come from the tiny fraction of the parent star's light that interacts with the planet on its journey towards Earth. The Hubble and Spitzer space telescopes have both detected gases such as carbon dioxide and water vapour in the atmospheres of a handful of gas-giant exoplanets as they pass in front of their parent stars. The gas molecules absorb light at characteristic wavelengths, and this shows up as dark lines in the spectrum of the starlight which has been filtered through the planet's atmosphere. But seeing evidence of life - so-called biosignatures - in the spectrum of worlds small enough to be rocky like Earth is beyond the sensitivity of these instruments.
Read more ....
No comments:
Post a Comment