Posted on 02/18/2011 10:01:33 AM PST by LibWhacker
ESA’s Herschel space telescope has discovered that previously unseen distant galaxies are responsible for a cosmic fog of infrared radiation. The galaxies are some of the faintest and furthest objects seen by Herschel, and open a new window on the birth of stars in the early Universe.
Astronomers estimate that their are billions and billions of galaxies in the observable universe (as well as some seven trillion dwarf galaxies) . Here's the breakout of the visible universe within 14 billion light years:
Superclusters in the visible universe = 10 million
Galaxy groups in the visible universe = 25 billion
Large galaxies in the visible universe = 350 billion
Dwarf galaxies in the visible universe = 7 trillion
Stars in the visible universe = 30 billion trillion (3x10²²)
Astronomers realized this past year that they may have underestimated the number of galaxies in some parts of the universe by as much as 90 percent, according to a study reported by Matthew Hayes of the University of Geneva's observatory, who led the investigation using the world's most advanced optical instrument -- Europe's Very Large Telescope (VLT) in Chile, which has four 8.2-meter (26.65-feet) behemoths. They turned two of the giants towards a well-studied area of deep space called the GOODS-South field.
In the case of very distant, old galaxies, the telltale light may not reach Earth as it is blocked by interstellar clouds of dust and gas -- and, as a result, these galaxies are missed by the map-makers.
"Astronomers always knew they were missing some fraction of the galaxies... but for the first time we now have a measurement. The number of missed galaxies is substantial," said Matthew Hayes of the University of Geneva's observatory, who led the investigation.
The team carried out two sets of observations in the same region, hunting for light emitted by galaxies born 10 billion years ago.The first looked for so-called Lyman-alpha light, the classic telltale used to compile cosmic maps, named after its U.S. discoverer, Theodore Lyman. Lyman-alpha is energy released by excited hydrogen atoms. The second observation used a special camera called HAWK-1 to look for a signature emitted at a different wavelength, also by glowing hydrogen, which is known as the hydrogen-alpha (or H-alpha) line.
The second sweep yielded a whole bagful of light sources that had not been spotted using the Lyman-alpha technique.
They include some of the faintest galaxies ever found, forged at a time when the universe was just a child.
The astronomers conclude that Lyman-alpha surveys may only spot just a tiny number of the total light emitted from far galaxies. Astonishingly, as many as 90 percent of such distant galaxies may go unseen in these exercises.
"If there are 10 galaxies seen, there could be a hundred there," said Hayes.
The discovery could add powerfully to knowledge about the timeline by which stars and then galaxies formed.
All I want is a planet of my own with no liberal or progressives, look at em’ all out there and I’m stuck on this mess, uggh !!
N = the number of civilizations in our galaxy with which communication might be possible; and
R* = the average rate of star formation per year in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fℓ = the fraction of the above that actually go on to develop life at some point
fi = the fraction of the above that actually go on to develop intelligent life
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space L = the length of time for which such civilizations release detectable signals into space.[3]
It seems to me the number of galaxies just shot up by...billions AND the number of Goldilocks planets keeps going up - I would think the odds have gone from puny to perhaps "small".
Does this explain the “dark matter” idea the astronomers used to account for the matter in the universe they couldn’t see?
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Well, biology is one thing, but laws of physics is another.
Strong Force is about 10 to the power of 100 times stronger than gravity is. So those are pretty small chances that both gravity and strong force have the exact right strength for the universe to exist.
Then you have to consider for the strength of weak force, electromagnetism, the velocity of the expansion of the universe, and numerous other factors to take into account for the existance of the universe as it is in the first place.
How long will it take me to hitch hike across it?
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