‘Smith Cloud’ is plummeting toward our galaxy at nearly 700,000 miles per hour
According to Hubble Space Telescope astronomers, the popular old saying that ‘what goes up must come down’ is even applicable on a huge cloud of hydrogen gas beyond our Milky Way galaxy. The invisible cloud is falling in the direction of our galaxy at roughly 700,000 miles per hour.
There are a large number of huge, high-velocity gas clouds speeding around the outskirts of our galaxy, but the so-called ‘Smith Cloud’ is different as its trajectory is well known. New Hubble observations have suggested that it was launched from the galactic disk’s out regions, nearly 70 million years back. The cloud was found in the early 1960s by doctoral astronomy student Gail Smith, who spotted the radio waves emission form its hydrogen.
The cloud heading towards a collision course and will plow into the Milky Way's disk in nearly 30 million years. As per astronomers when such an event will happen, it will ignite a stunning burst of star formation, probably providing sufficient gas for the formation of 2 million Suns.
Team leader Andrew Fox of the Space Telescope Science Institute in Baltimore, Maryland, explained, “The cloud is an example of how the galaxy is changing with time. It's telling us that the Milky Way is bubbling, very active place where gas can be thrown out of one part of disk and then return back down into another”.
Fox added that the Smith Cloud is among the examples that our galaxy has been recycling its gas via clouds, and is going to form stars in distinct places than before. He said that the measurements of the Smith Cloud taken by Hubble have been helping them in visualizing how active the disks of galaxies were.
The measurements taken by astronomers suggested that the comet-shaped region of gas is 11,000 light-years long and spread across 2,500 light-years.