From EsoCast in 1080p, comes the announcement of a rash of new planet discoveries. Astronomers using ESO's leading exoplanet hunter HARPS have today announced more than fifty newly discovered planets around other stars. Among these are many rocky planets not much heavier than the Earth. One of them in particular orbits within the habitable zone around its star.
Among the new planets just announced by scientists, sixteen are super-Earths - rocky planets up to ten times as massive as Earth. This is the largest number of such planets ever announced at one time.
A planet in orbit causes its star to regularly move backwards and forwards as seen from Earth. This creates a tiny shift of the star's spectrum that can be measured with an extremely sensitive spectrograph such as HARPS.
In their quest to find a rocky planet that could harbor life, astronomers are now pushing HARPS even further. They have selected ten well-studied nearby stars similar to our Sun. Earlier observations showed that these were ideal stars to examine for even less massive planets.
After two years of work, the team has found five light super-Earths around three of the stars. These planets are very good candidates for future observations looking for evidence of life.
One of the newly found planets, named HD 85512 b, orbits inside the habitable zone. This is the narrow area around a star where water can exist in liquid form. Astronomers estimate that liquid water could possibly be present on this planet if it is a rocky world that has more than 50% cloud cover.
By looking carefully at the results from the first 8 years of HARPS observations, the team has found that around 40% of stars similar to the Sun harbor at least one planet lighter than Saturn.
These new results lead astronomers to believe that they could soon find more super-Earths in the habitable zones of their stars with HARPS. These planets will be great targets for powerful future telescopes to try to study their atmospheres looking for evidence of life.
Thanks to HARPS, the search for another Earth elsewhere in the galaxy is picking up pace!
Information on TrES-2b, GSC 03549-02811, and Kepler Spacecraft. TrES-2b is the darkest known exoplanet. TrES-2b obits GSC 03549-02811 located 750 lightyears from Earth in the Draco constellation. TrES-2b was discovered on August 21, 2006 by the Trans-Atlantic Exoplanet Survey using Sleuth and PSST, part of the TrES network of 10-cm telescopes.