Changing Planet

Cosmic Crash at Milky Way Core?

This artist’s conception shows a supermassive black hole, with millions of times the mass of our sun, buried at the heart of our Milky Way galaxy. Credit: NASA

Astronomers around the world are on a cosmic stakeout, closely watching the supermassive black holelurking at the center of our Milky Way Galaxythat is about to gobble up an incoming gas cloud.

First spotted back in 2011, the blob of gas dubbed G2 appears poised for a suicidal plunge into the maw of the supermassive black hole called Sagittarius A* (Sgr A*). A monster of a black hole, it weighs in at about four million times the mass of our sun. Although it is a gas cloud, G2 hefts about three times the mass of Earth.

Currently G2’s distance from the black hole is equal to about 200 times the distance that Earth is from the sun, and it is spiraling in fast. It is expected to make its closest approach to the cosmic predator in the next two to three months.

When that happens, astronomers eagerly anticipate capturing their first ever glimpse of how a supermassive black hole gobbles up a cosmic snack. Astrophysicists hope to better understand not only how black holes grow and evolve, but also how matter reacts to extreme gravitational fields.

“Here we have an experiment where we get a chance to see how gas falls into a black hole,” said Leo Meyer, an astronomer at the University of California, Los Angeles, who spoke at a briefing at the meeting of the American Astronomical Society in Washington, D.C.

“These are fundamental physical processes that are not well understood, and we have a unique opportunity here to learn more about them.”

Located some 26,000 light-years from Earth, the Milky Way’s central black hole is hidden from clear view by dust and gas. However, astronomers can gaze behind the veil with infrared and x-ray telescopes. So, while backyard astronomers won’t be able to catch any of the possible brightening expected to occur as the blob of gas falls in toward the black hole, professional stargazers have both ground- and space-based telescopes trained on the soon-to-be-snacking beast.

Milky Way's galactic center as imaged by the Swift X-ray Telescope. This image is a montage of all data obtained in the monitoring program from 2006-2013. Credit: NASA/Swift/N. Degenaar (Univ. of Michigan)
Milky Way’s galactic center as imaged by the Swift x-ray telescope. This image is a montage of all data obtained by the monitoring program from 2006 to 2013. Credit: NASA/Swift/N. Degenaar (University of Michigan)

NASA’s orbiting Swift X-ray telescope has monitored the impending collision on a daily basis, for example, and astronomers are expecting to see a sudden brightening when it occurs.

The big question is whether there will be any fireworks when the blob meets its demise. That’s because astronomers aren’t sure if the blog is all gas, in which case it would glow bright, or is a star enshrouded in a gas cloud, in which case it would be quite a weak show.

“I would be delighted if Sagittarius A* suddenly became 10,000 times brighter. However, it is possible that it will not react much—like a horse that won’t drink when led to water,” Jon Miller, an astronomer at the University of Michigan, said in a press statement.

“If Sagittarius A* consumes some of G2, we can learn about black holes accreting at low levels—sneaking midnight snacks.”

Fireworks or fizzle, at this point astronomers have a front-row seat to see whatever will happen. Hopes are that within the next month or so, new observations will help astronomers narrow down the potential end game for G2.

“Will there be fireworks? The clear answer has to be: maybe,” says Meyer. “But this is a unique opportunity to learn something new in astrophysics.”

Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.

Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.
  • Booster Blake

    I really think the blackhole at the center of our own galaxy deserves a better name than Sagitarius A*. National Geographic should consider running a naming contest for this astounding core to our little island universe.

    Galacticore, Omnicore, Gravitros, Axistar, Kevin, etc.

  • Craig Lieberman

    The article implies we are waiting for an event to happen. The object is 26,000 light years away! The gas cloud was long gone before the pyramids, all known history, etc. The ‘event’ we are waiting for now is the delivery of the event horizon, which is the radiation from this event to reach our tiny little backwater planet.

  • tom

    I vote for Kevin…or maybe Lamar. Nobody names black holes Lamar any more…no idea why.

  • Shark

    The pictures are awesome

  • Some person

    We should call the black hole “Sagitarius A*, Destroyer of Worlds, Gas Clouds, and Other Extraterrestrial Objects, etc.” instead of just “Sagitarius A*”.

  • Steven hardaker

    No mention about the rareaty of other event horizen happenings in history. So unsure if G2 is a complete first about to be witnessed an if yes then all data/observations recorded is absolutly crucial when understanding our own supermassive in our back yard results will put weight on whats allready known an any understandment we know. But i will say this, be prepaird for the unknown and supprises when G2 is pulled in by Sgi A* with all astro-physicists, astrologists publicly showing detailed papers on the findings off data analasis with much evidence originally unknown to us thats exciting and answer questions asked in the most powerfull destructor in all the Universe. wer still not quite there in visually observing Sgr A*, untill more of our satalites/scopes come online with others around our planet allready in use together to gain enough power to focus on center of milky way and the outline of our “Supermassive Black hole” will for a world first be observed from earth. We must take every detailed second as new info received and all data recorded regarded as a new understandment in are biggest mystery ever descoverd. stars that orbit Sgr A* are moving at several Milions of Mph, and all we can see is these stars orbiting at center of milky way and only a BLK Hole has gravitational force in universe powerfull enough to pull stars so fast an its that exact understanding we can prove existence of Sgr A*, also in the detection of every Blk Hole found was proven by using the theory for orbiting stars and giant gas clouds at core ov so many galaxies can be seen orbiting “SOMETHING” at speeds of millions and millions of Mph. Only last decade we came to believe existence of black holes from seeing these celestial solar systems in close orbit and thats only how far we can go visually, but as earlier noted on future program, we as a planet are using ground based infared, radio and other satalites with high above sea level optical telescopes based at every corner ov the earth and using the power as a single scope on line alltogether to combine there capabilities to visually see past all gases, dust clouds, and light reflected and get outline of Sgr A* with an “Event Horizon” as it protrudes at the very top of rim where the gravity is infinte and end’s “ANYTHING” wen time xomes for thw next orbiting star or gases as when its dwvoierd closest in its orbit the milky way orbits its spiral arms spinning inevitablly to the black hole pulling in anything including full solar systems and basically stretch its next victim it pulled to the event horizon where gravity sucks object down into a point stretched out i think it is a illusion as if visioning it at its point it is stoped moving but up close the object is being torn appart due to Sgr A*’s infinate gravity “Spaghettisation” as officially named by the way it stretches inside to just a pinpoint at the bottom then projects out as nothing.
    Gas cloud G2 will answer questions we ask and finally tell WHAT HAPPENS NEXT?

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