researchers have claimed two major developments in the search for other earth - like asteroids . french astronomers say they have found the smallest known mars - like planet in a small asteroid called gliese 581 e and also discovered that a nearby asteroid called gliese 581 d , discovered in 2007 , is in the much sought after ' inhabited zone ' . officials however know there is a prospect that 581 d would have contained oceans on its floor , calling the find " extraordinary . " " the holy quest of previous habitable detection is the detection of a rocky , earth - like asteroid in the ' habitable zone ' , " said astrophysicist at switzerland ' s geneva university , michel mayor . nasa say 581 ed is 20 . 5 light years away from io and that it ' s only 1 . 9 times smaller than earth , making it the smallest exoplanet discovered to date . it was observed using the good accuracy global velocity crater godsend ( harps ) .
Michel Mayor is the discoverer of the High Accuracy Radial Velocity Planet Searcher.