Invisible galaxy crashing into Milky Way

A giant invisible galaxy is colliding with our Milky Way, astronomers have discovered. It is a vast cloud of hydrogen containing enough matter to make one hundred million suns - but has failed to produce any stars at all. The presence of the dark blob was first detected last year. But only now has it been identified as a giant galaxy.

It is a vast cloud of hydrogen containing enough matter to make one hundred million suns - but has failed to produce any stars at all.

The presence of the dark blob was first detected last year. But only now has it been identified as a giant galaxy.

Calculations by astronomers at Sydney, Australia, show that the object, called Smith's Cloud, is 100 times bigger than thought.

The cosmic crash is not a threat to stars in our own bigger galaxy but its gravitational pull will distort the shape of the Milky Way over millions of years.

http://www.scientificamerican.com/article.cfm?id=invisible-galaxy-crashing-into-milk-2009-11

LOL!

How can an absence of stars constitute a galaxy?

The Hubble Space Telescope has failed to reveal the expected number of stars in the mysterious, galaxy-sized cloud of hydrogen known as VIRGOHI21. The research bolsters the idea that the gas cloud is the only known example of a 'dark galaxy' that never kick-started star birth.

Galaxies are thought to coalesce from normal, or baryonic, matter that has collected in clouds of hypothetical dark matter. But surveys have turned up fewer galaxies than expected, suggesting that - for unknown reasons - some galaxies are stillborn, and simply fail to form stars.

The discovery of VIRGOHI21 in 2005 seemed to provide the first evidence that dark galaxies existed. However, a number of researchers suggested that VIRGOHI21 was pulled out of the nearby galaxy NGC 4254 when another galaxy called NGC 4262 shot past it at 900 kilometres per second. Indeed, NGC 4254 has a single prominent arm of stars that curls round towards VIRGOHI21, suggesting some sort of link between the two.

But Robert Minchin of the Arecibo Observatory discounts such "hit-and-run" models. "If the hydrogen in VIRGOHI21 had been pulled out of a nearby galaxy, the same interaction should have pulled out stars as well," says Minchin.

That ratio is much higher than expected - in all other galaxies, dark matter outweighs normal matter by a factor of only 10. "Even if this is a dark galaxy, it is not what you expect to find. The number of baryons is too low," says Michael Merrifield of the University of Nottingham in the UK, who was not on Minchin's team.

Minchin acknowledges that this is a puzzle. A number of surveys at Arecibo and other radio observatories aim to find more examples of dark galaxies, which could shed light on how much dark matter they contain. So far, however, the surveys are finding little to match the characteristics of VIRGOHI21.



http://www.newscientist.com/article/dn12100-dark-galaxy-continues-to-puzzle-astronomers.html

!

its a galaxy when its that big.

all you need is dust or gas to have a galaxy, its just a starless galaxy.

Man the straws! We'll make a fuel cell out of her yet!

:rofl:

So it'll look more like a Mounds?

I, for one, can't wait to see it.

:P

There were probably beautiful invisible unicorns somewhere in that too, I hope.

I can see the Creationists Translation of this now: God's giant invisible hand is spanking us for all the gay people. :eyes:

Yeah, sure... Smith, uh hunh...

Our galaxy is having an illicit affair.

that's what I'm betting on