Astronomers using the Hubble Space Telescope have found faint chemical traces of the Milky Way Galaxy lurking inside one of our cosmic neighbors, a massive, starless cloud hurtling through space at nearly 700,000 miles per hour. This object, known as the Smith Cloud, is unique among other so-called high velocity clouds because its orbit is well known. High-velocity clouds (HVCs) are large collections of gas found throughout the galactic halo of the Milky Way. New Hubble observations suggest it was launched from the outer regions of the galactic disk, around 70 million years ago. The cloud was discovered in the early 1960s by doctoral astronomy student Gail Smith, who detected the radio waves emitted by its hydrogen. It is now on a return collision course and is expected to plow into the Milky Way's disk in about 30 million years. When it does, astronomers believe it will ignite a spectacular burst of star formation, perhaps providing enough gas to make 2 million Suns. Release date: January 28, 2016.