... On October 1, 1847 Maria Mitchell swept the sky with her telescope and discovered a comet (comet Mitchell 1847VI). Moon Crashers . ... NGC 2346 is a planetary nebula made of gas and dust that has evolved into a familiar shape. ... Eta Carinae is the one of the most luminous star systems in our Galaxy, radiating millions of times more power than our Sun. ... Astronomers have discovered that looking at dust along the plane of our Milky Way Galaxy is a bit like looking into a frothy glass of beer. ...