... Surveyor At Mars . ... In the last few years, observational astronomy has given humanity evidence of the existence of worlds beyond the solar system. Solar-type stars are now inferred to harbor planets of approximately Jupiter mass - some residing in temperature zones which could conceivably support liquid water and therefore life! ... Comet Halley and the Milky Way . ... Comet Halley is the most famous comet in history, and returns to the inner Solar System every 76 years. ...