In Case You Missed It, A Giant Gas Cloud Is Hurtling Towards Our Galaxy At 700,000 Miles Per Hour

A giant gas cloud is on a collision course with the Milky Way, traveling at a staggering speed of 700,000 miles per hour, according to The Huffington Post.

But, don't fret, it is not going to strike against our planet any time soon, with scientists speculating that it may take up to 30 million years for the giant gas cloud to reach us.

As remarkable as that may sound, what is even more interesting is that Hubble Space Telescope astronomers believe that the giant gas cloud originated in our galaxy, the Milky Way, and is now boomeranging back. A classic case of what goes up must come down, isn't it?

When it returns to our galaxy, as Independent reports, "a spectacular burst of star formation" will take place, "perhaps providing enough gas to make 2 million stars." It will be a cosmic spectacle of unparalleled proportions, said Felix Lockman, a member of the team studying the cloud.

"Many of those stars will be very massive, rushing through their lives quickly and exploding as supernovae.

"Over a few million years, it'll look like a celestial New Year's celebration, with huge firecrackers going off in that region of the galaxy."

The giant gas cloud, or the Smith Cloud as it is known within the scientific community, was discovered mback in 1963, but its chemical composition remained a mystery for a long time. While a certain section of the scientific community believed that the giant gas cloud could be a starless galaxy or just a massive body of gas, a team of scientists from the University of Notre Dame in Indiana, led by Dr. Nicolas Lehner, have now successfully determined that it is made up of the same elements also found in the Sun, including sulfur.
According to their study, the giant gas cloud measures 11,000 light-years long and is 2,500 light-years wide, and is presently at a distance of only 8,000 light-years away from us. It is expected to strike our galaxy at an angle of 45 degrees, concluded Lockman.

"The leading edge of this cloud is already interacting with gas from our galaxy," he said.

Although astronomers are generally aware of the presence of most space clouds in the cosmic netherworld, the Smith Cloud is particularly unique because even its trajectory is well-known by scientists. Andrew Fox of the Space Telescope Science Institute in Baltimore, Maryland, said the discovery of the giant gas cloud's composition is interesting because it gives us an important perspective about our own galaxy, the Milky Way.

"The cloud is an example of how the galaxy is changing with time. 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."
Smith Cloud's Trajectory as released by NASA.
Smith Cloud's trajectory (Image via Hubble)

The astronomers discovered the composition of the giant gas cloud by observing the light from distant galaxies that passed through it. Having observed the wavelengths of the ultraviolet light that made it through the cloud, scientists concluded that it is made of sulfur, an element the outer disk of our Milky Way abounds in. This is how astronomers realized that the giant gas cloud was ejected by our galaxy millions of years ago, although the precise reason for its ejection is still shrouded in mystery.

The research team's study on the giant gas cloud, On the Metallicity and Origin of the Smith High-Velocity Cloud, was published this month in the Astrophysical Journal Letters.

The giant gas cloud might be some way off our galaxy as of now, but the discovery of its composition is another leap for astronomy.

[Image via NASA/Getty Images]