An illustration of the inivisible galaxy
The invisible galaxy could only be 'seen'
using radio waves
Posted on 02/23/2005 1:32:25 PM PST by LibWhacker
An illustration of the inivisible galaxy
The invisible galaxy could only be 'seen'
using radio waves
Astronomers say they have discovered an object that appears to be an invisible galaxy made almost entirely of dark matter.
The team, led by Cardiff University, claimed it is the first to be detected.
A dark galaxy is an area in the Universe containing a large amount of mass that rotates like a galaxy, but contains no stars.
It was found 50 million light years away using radio telescopes in Cheshire and Puerto Rico.
The unknown material that is thought to hold these dark galaxies together is known as 'dark matter', but scientists still know very little about what that is.
The five-year research has involved studying the distribution of hydrogen atoms throughout the Universe, estimated by looking at the rotation of galaxies and the speed at which their components moved.
Hydrogen gas releases radiation that can be detected at radio wavelengths.
In the Virgo cluster of galaxies, they found a mass of hydrogen atoms a hundred million times the mass of the Sun.
The mysterious galaxy has been called VIRGOHI21.
Similar objects that have previously been discovered have since turned out to contain stars or be remnants of two galaxies colliding.
However, the scientists from the UK, France, Italy and Australia found no visible trace of any stars, and no galaxies nearby that would suggest a collision.
Dr Robert Minchin, of Cardiff University, said: "From its speed, we realised that VIRGOHI21 was a thousand times more massive than could be accounted for by the observed hydrogen atoms alone.
"If it were an ordinary galaxy, then it should be quite bright and would be visible with a good amateur telescope."
The astronomers say it is hard to study the universe's dark, hidden objects because of the Earth's proximity to the Sun.
They liken it to looking out at the darkest night from a well-lit room - it is easy to make out street lights but not trees, hedges and mountains.
Astronomers say it marks an important breakthrough because, according to cosmological models, dark matter is five times more abundant than the ordinary (baryonic) matter that makes up everything we can see and touch.
Another of the Cardiff team, Dr Jon Davies, added: "The Universe has all sorts of secrets still to reveal to us, but this shows that we are beginning to understand how to look at it in the right way. It's a really exciting discovery."
bttt
Yeah, it's called Hollywood.
Beat me to it!
Should it be called "dim matter" rather than "dark matter"? In either case, interesting.
Okay, explain to those of us who are science-challenged: What the heck is dark matter?
I don't know either, but perhaps the could call it "The Emperor's New Galaxy!"
where's the link?
Jesse Jackson?
Have they considered a Black Hole which has already consumed all that was within it's gravitational pull?
Stuff that theoretically should be there, but isn't. Cuz they cannot see it, so it must be invisible, or dark.
Whatever.....
it looks like an 'ula 'oop
Well, hey, I found an invisible galaxy myself. Am hoping it will be named after me. Only problem is that to date, nobody else has been able to see it. Do you think I could get a grant to study it in more detail?
No, Jesse Jackson is Dark DOESN'T matter
Great, I guess they found the underverse.
So, using the term "matter" to describe it is probably not accurate. I imagine that once we get a better understanding of this stuff, it will have no relation to "matter" as we know it.
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