Milky Way Galaxy Doomed to Head-On Crash with Andromeda

Four billion years from now, the Milky Way galaxy as we know it will cease to exist.

Our Milky Way is bound for a head-on collision with the similar-sized Andromeda galaxy, researchers announced today (May 31). Over time, the huge galactic smashup will create an entirely new hybrid galaxy, one likely bearing an elliptical shape rather than the Milky Way's trademark spiral-armed disk.

"We do know of other galaxies in the local universe around us that are in the process of colliding and merging," Roeland van der Marel, of the Space Telescope Science Institute in Baltimore, told reporters today. "However, what makes the future merger of the Andromeda galaxy and the Milky Way so special is that it will happen to us."

Astronomers have long known that the Milky Way and Andromeda, which is also known as M31, are barrelling toward one another at a speed of about 250,000 mph (400,000 kph). They have also long suspected that the two galaxies may slam into each other billions of years down the road. [Milky Way Slams Into Andromeda (Artist Images)]

However, such discussions of the future galactic crash have always remained somewhat speculative, because no one had managed to measure Andromeda's sideways motion —  a key component of that galaxy's path through space.

But that's no longer the case.

Van der Marel and his colleagues used NASA's Hubble space telescope to repeatedly observe select regions of Andromeda over a seven-year period. They were able to measure the galaxy's sideways (or tangential) motion, and they found that Andromeda and the Milky Way are indeed bound for a direct hit.

"The Andromeda galaxy is heading straight in our direction," van der Marel said. "The galaxies will collide, and they will merge together to form one new galaxy." He and his colleagues also created a video simulation of the Milky Way crash into Andromeda.

That merger, van der Marel added, begins in 4 billion years and will be complete by about 6 billion years from now.

A future cosmic crash

Such a dramatic event has never occurred in the long history of our Milky Way, which likely began taking shape about 13.5 billion years ago.

"The Milky Way has had, probably, quite a lot of small, minor mergers," said Rosemary Wyse of Johns Hopkins University in Baltimore, who was not affiliated with the new study. "But this major merger will be unprecedented."

The merger poses no real danger of destroying Earth or our solar system, researchers said. The stretches of empty space separating the stars in the two galaxies will remain vast, making any collisions or serious perturbations unlikely.

However, our solar system will likely get booted out to a different position in the new galaxy, which some astronomers have dubbed the "Milkomeda galaxy." Simulations show that we'll probably occupy a spot much farther from the galactic core than we do today, researchers said.

A new night sky

And the collision will change our night sky dramatically. If any humans are still around 3.75 billion years from now, they'll see Andromeda fill their field of view as it sidles up next to our own Milky Way. For the next few billion years after that, stargazers will be spellbound by the merger, which will trigger intense bouts of star formation.

Finally, by about 7 billion years from now, the bright core of the elliptical Milkomeda galaxy will dominate the night sky, researchers said. (The odds of viewing this sight, at least from Earth, are pretty slim, since the sun is predicted to bloat into a huge red giant 5 or 6 billion years from now.)

In its 22-year history, Hubble has revolutionized the way humanity views the cosmos. The new finding is another step in that process, researchers said.

"What's really exciting about the current measurements is, it's not about historical astronomy; it's not about looking back in time, understanding the expansion of the universe," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate and a former astronaut who flew on three space shuttle missions that repaired Hubble .

"It's looking forward in time, which is another very human story," Grunsfeld added. "We like to know about our past — where did we come from? We very much like to know where we're going."

You can follow SPACE.com senior writer Mike Wall on Twitter: @michaeldwall. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

Copyright 2012 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Loading...

Editor’s note:Yahoo Philippines encourages responsible comments that add dimension to the discussion. No bashing or hate speech, please. You can express your opinion without slamming others or making derogatory remarks.

  • Philippines accuses China of turning water cannon on its fishing boats

    Filipino activists denounced China's coast guard on Tuesday for turning water cannon on Philippine fishing boats in disputed waters, near where hundreds of Filipino and American Marines landed on a beach in a mock assault. The presidential palace in Manila said China's coast guard used water cannon on Monday to drive away a group of Filipino fishermen at Scarborough Shoal, damaging some of their wooden boats. …

  • U.S. says if China used water cannons on Philippine boats, would be provocative'

    The U.S. State Department said on Tuesday that if reports that China used water cannon son Philippine fishing boats in disputed waters are accurate, it would be a provocative step. Filipino activists have accused China's coast guard of turning water cannons on civilian boats in the disputed area on Monday. …

  • Pacmania sweeps Philippines ahead of Mayweather clash
    Pacmania sweeps Philippines ahead of Mayweather clash

    Manny Pacquiao's face is on shirts, dolls and postage stamps, his life story is playing in movie houses and millions are getting ready to party as the Philippine boxing hero's "fight of the century" nears. Pacmania is sweeping the Southeast Asian nation of 100 million people ahead of the May 2 Las Vegas bout against unbeaten Floyd Mayweather to decide who is the best boxer of their generation. Of course, it's the fight of the century," Manila film producer Lucky Blanco told AFP. …

  • ‘Racist remark vs Pinays not reflective of HK sentiment’
    ‘Racist remark vs Pinays not reflective of HK sentiment’

    The Philippine consulate general in Hong Kong believes that the “racist” statement of legislator Regina Ip against Filipina domestic helpers in Hong Kong is not reflective of the general sentiments of the Hong Kong community. Hong Kong is home to more than 173,00 Filipinos working mostly as household service workers. “They have left their loved ones back home to earn a decent living taking care of Hong Kong families. This, in turn, has engendered positive impact on both the quality of life …

  • SWS: Gov’t rating sinks to record low
    SWS: Gov’t rating sinks to record low

    “The Aquino administration is firmly determined to carry on and complete priority programs in all five pillars of the Philippine development plan, to ensure that reforms will be sustained by strengthened public institutions, to tread the righteous path and ensure that good governance becomes the norm at all levels of government, and to sustain and make permanent the gains from the transformation of mindsets and institutions,” Coloma added. Lawmakers expressed belief yesterday that the Aquino …

  • ‘Pacmania’ sweeping the nation
    ‘Pacmania’ sweeping the nation

    Manny Pacquiao’s face is on shirts, dolls and postage stamps, his life story is playing in movie houses, and millions are getting ready to party as the Philippine boxing hero’s “fight of the century” nears. Pacmania is sweeping the nation of 100 million people ahead of the May 2 Las Vegas bout against unbeaten Floyd Mayweather Jr. to decide who is the best boxer of their generation. …

  • House committee to put Bangsamoro police under PNP
    House committee to put Bangsamoro police under PNP

    The House ad hoc committee on the proposed Bangsamoro Basic Law (BBL) will put police forces in the envisioned new autonomous Muslim region under the Philippine National Police (PNP), and not under the regional chief minister. “We will delete the provision in the draft BBL giving the chief minister operational, administrative and disciplinary control over police forces in the region,” Cagayan de Oro City Rep. Rufus Rodriguez, committee chairman, said in a television interview. He said under …

  • Phl to seek more US military aid
    Phl to seek more US military aid

    The Philippines said yesterday it would soon ask the United States for more military equipment and training to build its defenses, as it faces Chinese “aggressiveness” in disputed waters. As hundreds of Filipino and American Marines simulated an amphibious assault to reclaim territory from invaders during annual war games, Armed Forces chief Gen. Gregorio Pio Catapang said he was drafting a “wish list” for US aid. Catapang said the Philippines would ask for “equipment and training” when …

POLL

Should Aquino be held accountable over the Mamasapano operations?

Loading...
Poll Choice Options