One of the most extraordinary experiments in the history of science was carried out in 1993 when the NASA spacecraft Galileo flew past Earth on its way to Jupiter. Carl Sagan and pals analysed the data and concluded after much head scratchin that life on Earth was a distinct possibility.<\/p>\n
That was a dry run for the real thing which we’re about to embark on big time. Astrobods have found more than 260 extrasolar planets and now ya’ll wanna know whether any of them are packing slime worth bothering about.<\/p>\n
We got several spacecraft in the pipeline such as Darwin and the Terrestrial Planet Finder (TPF) that are gonna start the task of analysing the atmospheres of these lands and Lisa “King” Kaltenegger at the Harvard-Smithsonian Center from Astrophysics wants to know whether they’re up to the job.<\/p>\n
She reckons the most important factors will be determining the planets’ sizes and temperatures. Beyond that she says it will be important to spot biomarkers such as the spectral signatures of oxygen, ozone and methane (which assumes, of course, that extra-solar life is carbon-based and dependent on water, just like us). Her conclusion is that the next generation of spacecraft have got a good chance of spotting all these things…if they’re out there.<\/p>\n