Posted on 08/07/2006 1:55:19 PM PDT by NormsRevenge
A project aiming to create an easier way to measure cosmic distances has instead turned up surprising evidence that our large and ancient universe might be even bigger and older than previously thought.
If accurate, the finding would be difficult to mesh with current thinking about how the universe evolved, one scientist said.
A research team led by Alceste Bonanos at the Carnegie Institution of Washington has found that the Triangulum Galaxy, also known as M33, is about 15 percent farther away from our own Milky Way than previously calculated.
The finding, which will be detailed in an upcoming issue of Astrophysical Journal, suggests that the Hubble constant, a number that measures the expansion rate and age of the universe, is actually 15 percent smaller than other studies have found.
Currently, most astronomers agree that the value of the Hubble constant is about 71 kilometers per second per megaparsec (a megaparsec is 3.2 million light-years). If this value were smaller by 15 percent, then the universe would be older and bigger by this amount as well.
Scientists now estimate the universe to be about 13.7 billion years old (a figure that has seemed firm since 2003, based on measurements of radiation leftover from the Big Bang) and about 156 billion light-years wide.
The new finding implies that the universe is instead about 15.8 billion years old and about 180 billion light-years wide.
A new way to measure distance
The researchers reached their surprising conclusion after using a new method they invented to calculate intergalactic distances, one that they say is more precise and requires fewer steps than standard techniques.
"We wanted an independent measure of distance--a single step that will one day help with measuring dark energy and other things," said study team member Krzysztof Stanek from Ohio State University.
The new method took 10 years to develop and relied on optical and infrared measurements gathered from telescopes all around the world. The researchers looked at a binary star system in M33 where the stars eclipsed each other every five days. Unlike single stars, the masses of paired stars can be precisely calculated based on their movements. With knowledge of the stars' masses, the researchers could calculate their true luminosities, or how bright they would appear if they were nearby.
The difference between the true luminosity and the observed luminosity gives the distance between the stars and Earth. The team's results suggested that the stars were about 3 million light-years from Earth--or about half-a-million light-years farther than would be expected using the commonly accepted Hubble constant value.
'Not impossible'
Lawrence Krauss, a professor of astronomy and chair of the Department of Physics at Case Western Reserve who was not involved in the study, said the idea of a significantly reduced Hubble constant would be hard to accommodate.
"Things fit right now very well for a Hubble constant of a low 70s," Krauss said in a telephone interview. "It corresponds very well with the age of globular clusters as we've determined them and the age of the universe. It would be hard, although not impossible, to change things by 15 percent."
Stanek said his team plan to follow up their finding with distance measurements for either another binary star system in M33 or to look for a binary system in another galaxy, perhaps Andromeda.
"It's extremely important to have independent measurements of the Hubble constant," Stanek told SPACE.com. "That's what we're working towards."
"Can someone explain this problem?
1. The speed of light is suppose to be a constant at 299,792,458 m/s.
2. The size of the universe is suppose to be billions of light years across.
3. The universe is suppose to have expanded to close to its present size during the 'Big Bang' in a fraction of a second.
"
The size of the visible universe is a little bigger than the Hubble volume. But, and this is usually, almost invariably, ignored, the whole universe by the popular model has a radius 25 billion times larger than the Hubble radius. The rest is not visible because it is moving away from us faster than the speed of light and always was after the inflation phase of the Big Bang was underway.
BTW, the speed of light is not the sacred limit of all possible speed in the Theory of Relativity either, even though popular legend says it is.
The entity that "exploded" in the Big Bang was a singularity prior to the Big Bang, and conventional physics don't apply to singularities (or so I've heard).
The Big Bang Theory: First there was nothing, then it blew up.
Is C the limit for things with mass? Isn't there something called a nutrino that has almost no mass and besides being able to pass through the earth, can also travel faster than C?
LOL!
You were gonna go fishin', wernt ya?
That's not it. Relativity could have been developed with the speed of sound as an example, but the author chose electromagnetism because it was more interesting to him. It's just an example that took care of some inconsistencies involving propagation of light, which was the hot issue of the day.
And it seems like a lot of the current theories, e.g. dark matter, are being cobbled together out of nothing, with no evidence that it actually exists, to explain something else. I think the need to re-check their math.
Abaal the size of earth made out of steel. Once a year a bird lands on it and sharpens his beak for a few secs. It will take an eternity for the ball to be whittled away to nothing.
PIMF
This would happen just as gas hits an all time high!
And if the universe is bigger and older than previously thought, so what? Why is that newsworthy? Years ago, I was at a planetarium show about the age and fate of our universe. At one point the narrator said that, in about 8 billion years, the sun would burn out and our solar system would perish. Somebody not paying close attention raised a hand to ask about that time frame. The narrator repeated the 8 billion years reference. The questioner breathed a sigh of relief and said, "Whew! I thought you said, 6 billion years!"
"3. The universe is suppose to have expanded to close to its present size during the 'Big Bang' in a fraction of a second."
I think your #3 is wrong. The expansion was fast to begin with, but not to include current galaxies, of which there are billions. And the expansion is ongoing.
From various books, I get the impression that our "universe" is but one of an infinite number of universes, and there are more dimensions of space than the three we are familiar with - some say ten - plus "time".
Of the three, Alceste would definitely be MY first choice...
What if the bird came once every two years? Wouldn't it take twice as long?
The universe has been expanding since the big bang. The wierd thing is, it appears to be accelerating. Dark matter/dark energy may be the cause.
That's what they said about me last time I went to the doctor's office.
So, if I understand you correctly.
The speed of light is a slowly changing variable contrary to how its popularly defined as a constant.
During the Universe's beginnings the speed of light could have been vastly different than presently observed.
Hummm.. Bigger than what?... Older than what?...
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