The cosmic cloud is heading for us at more than 240km/s
Posted on 01/12/2008 9:49:08 AM PST by Ernest_at_the_Beach
The cosmic cloud is heading for us at more than 240km/s
A giant cloud of hydrogen gas is racing towards a collision with the Milky Way, astronomers have announced.
Smith's Cloud, as it is known, may set off spectacular fireworks when it smacks into our galaxy in 20-40 million years.
It contains enough hydrogen to make a million stars like the Sun, say experts, and its leading edge is already hitting gas from our galaxy.
When it does hit, the cloud could indeed set off a new burst of star formation in the Milky Way.
Details of the work, by a team at the US National Radio Astronomy Observatory and the University of Wisconsin-Whitewater, were unveiled at the 211th meeting of the American Astronomical Society in Austin, Texas.
Impressive sight
Smith's Cloud is named after the astronomer who discovered it in 1963. But until now, astronomers had no idea whether it was leaving the Milky Way or falling into it.
The new work by a team using the Green Bank telescope (GBT) in West Virginia to observe the object shows, unmistakably, that the latter is true.
Astronomers have taken detailed images of the cloud
Their new measurements also show that the cloud is 11,000 light-years long and 2,500 light-years wide. The monster cosmic "fog bank" is careering towards our galaxy at more than 240km/s (150 miles/s) and is set to strike the Milky Way at an angle of 45 degrees.
Broadly speaking, the cloud is currently rotating with our galaxy, but is also moving in towards it. Astronomers can see a wall of gas being ploughed up as Smith's Cloud thuds into the outskirts of our galaxy's atmosphere.
Lead author Dr Felix Lockman, from the NRAO, said the object, which lies at a distance of 40,000 light-years from Earth, would make an impressive sight if it could be seen with the naked eye.
"We don't know quite where it came from yet, as its orbit is a little confused, but we can tell it is beginning to interact with the outskirts of the Milky Way, that it is suffering drag and that bits of it are falling off," Dr Lockman told the BBC News website.
"But at the same time, it is feeling the gravitational pull of the Milky Way and is plunging in towards the disc."
By the time it merges with our galaxy, Smith's cloud will strike a region some distance from the location of our Solar System, about 90 degrees ahead of us in the disc of the Milky Way.
Celestial New Year
Where it does collide, the cloud will generate shockwaves in the gas already residing in the Milky Way.
"It will be just like letting a bomb go off," said Dr Lockman, "but you also create a lot of new gas which may have different properties to the existing gas.
The shockwaves will set off a tremendous burst of star formation. These stars will be massive, rushing through their lives quickly and exploding as supernova.
"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," said Dr Lockman.
Co-author Dr Robert Benjamin, from the University of Wisconsin-Whitewater, told BBC News: "If the drag is sufficient, and the cloud fragments, there could be less of an effect. But at the moment, it looks like it is holding together quite tightly."
Astronomers have previously surmised that a region of bright stars called Gould's Belt, which lies close to our own Sun, could have been created in just this way.
"This is the first time we're actually seeing it happen," said Dr Lockman.
"The Milky Way is still under bombardment - there are still fragments of it coming in and arriving on the scene. When this happens, it can bring fresh gas and trigger new star formation. And it's interesting to speculate whether this [once] happened near the Sun."
The gas cloud was discovered in 1963 by the young American astronomer Gail Smith working at Leiden University in the Netherlands. She subsequently left science but still lives in the Netherlands.
Paul.Rincon-INTERNET@bbc.co.uk
Like on Star Trek:TNG, they just need to inject some reactant element into the approaching cloud to ignite it, then everyone can get some sleep....
It’s all Bush’s fault, you know...
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the newer topic:
Cosmic Cloud on Collision Course
ScienceNOW Daily News | 11 January 2008 | Govert Schilling
Posted on 01/12/2008 2:20:45 PM EST by placerville
http://www.freerepublic.com/focus/news/1952655/posts
He saved it from being shut down.
..............Technically, it is named the Robert C. Byrd Green Bank Telescope.
He saved it from being shut down.
...........................
Aw Com’on, you’re kiddin’ me??
Sorry, I can't wait. I have an appointment...
Damn Man Made Galactic Warming! Al Gore save us!
Who needs Rick Hunter? Just play a tape of Minmei singing “To Be In Love...”
hang on a sec, I've got a pic of that somewhere...
here 'tis:
We can prevent this. All we need to do is write a check to Al Gore.
once upon a long long time ago...when Earth was smaller, there were no oceans at all.
Hmmmm. What shall I make of that picture?
Must be that Expanding Earth thing again....LOL!
Interesting view without the water, (and sediment)isn't it?
Couldn't they refine it a little more than that? Like, say, within a million years or so? How's a feller supposed to enter this in his appointment calendar?
We used to make maps of Alaska out of scrap from the 48” pipe when we worked at Prudhoe. Looked a lot like that piece of art.
“Must be that Expanding Earth thing again....LOL!”
http://ourworld.compuserve.com/homepages/dp5/tecto.htm
Abstract. – This paper looks at the challenges confronting plate tectonics – the ruling paradigm in the earth sciences. The classical model of thin lithospheric plates moving over a global asthenosphere is shown to be implausible. Evidence is presented that appears to contradict continental drift, seafloor spreading and subduction, and the claim that the oceanic crust is relatively young. The problems posed by vertical tectonic movements are reviewed, including evidence for large areas of submerged continental crust in today’s oceans. It is concluded that the fundamental tenets of plate tectonics might be wrong.
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