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A massive cloud of hydrogen is hurtling toward the Milky Way at close to 700,000 miles per hour, according to new research published in a recent edition of the Astrophysical Journal Letters .

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/gas-cloud.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/gas-cloud.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/gas-cloud.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > The Smith Cloud, a humongous collection of hydrogen, might be returning to our galaxy in about 30 million years. (NASA)

The Smith Cloud was discovered in the early 1960s by doctoral astronomy student Gail Smith, who detected the radio waves emitted by its hydrogen.

Hubble Space Telescope observations suggest that the cloud emanated from the outer edge of the Milky Way some 70 million years ago.

The cloud is on a return collision course and is expected to plow into the Milky Way’s disk in about 30 million years, according to NASA scientists. When it does, astronomers believe it will ignite a spectacular burst of star formation, perhaps providing enough gas to make 2 million suns.



Andrew Fox, with the Space Telescope Science Institute, said, “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."

Though invisible, false-color images of the cloud have been rendered by the space agency, showing the cloud's trajectory over time and size relative to Earth's moon when full.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/smith-cloud.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/smith-cloud.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/smith-cloud.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" >

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