sentence1: Scientists have made two major discoveries in the search for other Earth-like planets. British astronomers say they have discovered the smallest known Earth-like exoplanet orbiting a living star called Gliese 581 e and also discovered that a nearby planet called Gliese 581 d, discovered in 2007, is in the much sought after 'habitable zone'. Astronomers also believe there is a possibility that 581 d could have liquid oceans on its surface, calling the find "extraordinary."  "The Holy Grail of current exoplanet research is the detection of a rocky, Earth-like planet in the 'habitable zone'," said astrophysicist at Switzerland's Geneva University, Michel Mayor.  Astronomers say 581 e is 20.5 light years away from Earth and that it's roughly 1.9 times larger than Earth, making it the smallest exoplanet discovered to date. It was found using the High Accuracy Radial Velocity Planet Searcher (HARPS).
sentence2: Michel Mayor is the discoverer of the High Accuracy Radial Velocity Planet Searcher.