signs of life on other planets within 20 years- Space/Astronomy

Space/Astronomy Stars, Planets, and Galaxies Hints, Tips, and Equipment for Stargazers New Discoveries in Astronomy Space Exploration Observatories and Space Missions Tools and Equipment for Astronomy Basic Resources for Astronomy and Space Does Life Exist Elsewhere in Our Galaxy? The Search for Alien Life in the Far Reaches of Space SHARE PIN EMAIL By John P. Millis, Ph.D, Space/Astronomy Expert The search for life outside our tiny blue rock has consumed the imagination of man for decades. But now, with increasingly advanced technology we may finally be on the verge of discovering where else life may exist in our galaxy. The more we search, however, the more we realize that life may be rather precious after all. There have already been claims of detection, mostly met with controversy for one reason or another.And accompanying said claims comes the unfounded declarations that life must also exist on these worlds. But just because we find a planet that appears fit for life, and I am sure that we will in the not too distant future make such a discovery, does it mean necessarily that life does exist there?“Our own galaxy has 100 billion stars and our universe has upwards of 100  billion galaxies — making the chance for life elsewhere seem inevitable based on sheer probability,” said Dr Seager. In the next decade or two, a handful of “potentially habitable” exoplanets — planets that do not orbit the Sun but a different star — will have been found with atmospheres that can be studied in detail by sophisticated space telescopes, she said. The first of these “next generation” telescopes will be Nasa’s James Webb Space Telescope, due to launch in 2018. It will be able to analyse the atmospheres of dozens of “super-Earths” —rocky planets somewhat larger than Earth — including several that could harbour life. Studying a planet’s atmosphere for signs of life involves capturing starlight filtering through its gases. Different elements absorb different wavelengths of light, providing information about the atmosphere’s make-up. Living things, from bacteria to large animals, are expected to produce “biosignature” gases that could be detected in a planet’s atmosphere. These include oxygen, ozone, nitrous oxide, and methane. The problem faced by scientists is that some of these, such as methane, can be generated by geological processes as well as life. The likelihood of “false positives” could be reduced by searching for rarer biosignature gases, said Dr Seager. She added: “We stand on a great threshold in the human history of space exploration. If life is prevalent in our neighbourhood of the galaxy, it is within our reach to be the first generation in human history to finally cross this threshold and learn if there is life of any kind beyond Earth.