A monstrous region of hydrogen gas officially named the Smith Cloud, cruising along at the far borders of our galaxy, is boomeranging back toward the Milky Way at breakneck speed. But worry not! Even though this starless galactic remnant once ejected by our spiral galaxy is hurtling into our neighborhood at the rate of 700,000 miles per hour, astronomers calculate it won't reach our vicinity for another 30 million years, when its gaseous presence could be the epic catalyst for the formation of up to 2 million new suns.
As captured by the Green Bank Telescope in West Virginia, this false-color image of the comet-shaped cloud is revealed as radio wavelengths measuring approximately 11,000 light-years long and 2,500 light-years across. The visible-light image of the background star field identifies the Smith Cloud's location as being in the proximity of the constellation Aquila. First discovered in 1960 by doctoral astronomy student Gail Smith, recent Hubble Space Telescope measurements show that the cloud came out of a remote region near the edge of the galaxy's disk of stars some 70 million years ago.
“The cloud is an example of how the galaxy is changing with time,” explained team leader Andrew Fox of the Space Telescope Science Institute in Baltimore, Md. “It’s telling us that the Milky Way is a bubbling, very active place where gas can be thrown out of one part of the disk and then return back down into another. Our galaxy is recycling its gas through clouds, the Smith Cloud being one example, and will form stars in different places than before. Hubble’s measurements of the Smith Cloud are helping us to visualize how active the disks of galaxies are."
If predictions come true millions of years hence, prime galactic real estate values after the Smith Cloud returns should be stellar.