Jump to content




Welcome to Unexplained Mysteries! Please sign in or create an account to start posting and to access a host of extra features.


- - - - -

Universe bigger and older than thought


  • Please log in to reply
6 replies to this topic

#1    Roj47

Roj47

    Psychic Spy

  • Member
  • PipPipPipPipPipPipPipPip
  • 1,149 posts
  • Joined:03 Jan 2006
  • Gender:Male
  • Location:Newton Aycliffe, Leeds and Middlesbrough

  • If I believed the world was going to end in the next 10 years..... I would sell up and travel to see as much of it as I could.

Posted 08 August 2006 - 03:08 PM

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.



http://www.space.com/scienceastronomy/0608...ble_revise.html

Posted Image
Posted Image

#2    Atheist God

Atheist God

    Alien Abducter

  • Member
  • 5,438 posts
  • Joined:10 Jul 2006
  • Gender:Male
  • Location:Winnipeg, Canadistan

  • At war with the evil Drug Enforcement Agency for over a decade!

Posted 09 August 2006 - 02:13 AM

I read this article also and it made me think that perhaps other calculations made by scientists have benn innaccurate over the years.

Posted Image

A site I write my own articles. sw-gm check em out.

#3    Waspie_Dwarf

Waspie_Dwarf

    Space Cadet

  • 32,169 posts
  • Joined:03 Mar 2006
  • Gender:Male
  • Location:Bexleyheath, Kent, UK

  • We are all in the gutter, but some of us are looking at the stars.

    Oscar Wilde

Posted 09 August 2006 - 02:20 AM

Quote


I read this article also and it made me think that perhaps other calculations made by scientists have benn innaccurate over the years.


Of course some are. If science knew every thing the research scientists could all pack up and retire. Science is a continuing search for knowledge. New theories over take old. Newton was replaced by Einstien. But with each new discovery the depth of human knowledge increases slightly. If you want "absolute truth" then that is the realm of religion.

Edited by Waspie_Dwarf, 09 August 2006 - 02:27 AM.

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

Posted Image
Click on button

#4    Startraveler

Startraveler

    Fleet Captain

  • Member
  • 4,524 posts
  • Joined:25 Jun 2006
  • Gender:Male
  • Location:New England

  • Knowledge Brings Fear.

Posted 10 August 2006 - 01:52 AM

I put this in the other thread (in Main News) but since there are two threads I must as well include it here as well. It was announced yesterday that a study using the Chandra X-ray observatory has used a unique method to measure the Hubble constant; their results are in line with the consensus value:

Quote

By combining X-ray data from Chandra with radio observations of galaxy clusters, the team determined the distances to 38 galaxy clusters ranging from 1.4 billion to 9.3 billion light years from Earth. These results do not rely on the traditional distance ladder. Bonamente and his colleagues find the Hubble constant to be 77 kilometers per second per megaparsec (a megaparsec is equal to 3.26 million light years), with an uncertainty of about 15%.

This result agrees with the values determined using other techniques. The Hubble constant had previously been found to be 72, give or take 8, kilometers per second per kiloparsec based on Hubble Space Telescope observations. The new Chandra result is important because it offers the independent confirmation that scientists have been seeking and fixes the age of the Universe between 12 and 14 billion years.

"These new results are entirely independent of all previous methods of measuring the Hubble constant," said team member Marshall Joy also of MSFC.

The astronomers used a phenomenon known as the Sunyaev-Zeldovich effect, where photons in the cosmic microwave background (CMB) interact with electrons in the hot gas that pervades the enormous galaxy clusters. The photons acquire energy from this interaction, which distorts the signal from the microwave background in the direction of the clusters. The magnitude of this distortion depends on the density and temperature of the hot electrons and the physical size of the cluster. Using radio telescopes to measure the distortion of the microwave background and Chandra to measure the properties of the hot gas, the physical size of the cluster can be determined. From this physical size and a simple measurement of the angle subtended by the cluster, the rules of geometry can be used to derive its distance. The Hubble constant is determined by dividing previously measured cluster speeds by these newly derived distances.


Press release


#5    ivytheplant

ivytheplant

    Knows what you're up to

  • Member
  • PipPipPipPipPipPipPipPip
  • 1,509 posts
  • Joined:25 Apr 2006
  • Gender:Female
  • Location:Ivytopia

  • Nothing is impossible, only improbable.

Posted 10 August 2006 - 05:08 PM

So the universe was previously 13 and decided it didn't look old enough and wanted to be 15? How long before it can get into rated R movies. wink2.gif

Man, just when I think I finally have the geologic time scale and age of the universe finally memorized...

"I reject your reality and substitute my own." - Adam Savage, Mythbusters

#6    Startraveler

Startraveler

    Fleet Captain

  • Member
  • 4,524 posts
  • Joined:25 Jun 2006
  • Gender:Male
  • Location:New England

  • Knowledge Brings Fear.

Posted 12 August 2006 - 11:47 PM

Little bit more news today (or yesterday, I suppose). Three of the coauthors on the paper the space.com article is about, including Kris Stanek, have coathored another paper that'll soon be published in the Astrophysical Journal on calibrating the Cepheid distance scale. Cepheids are variable stars that have a certain relation between their period of variability and their absolute magnitude. Thus by observing how long a Cepheid's bright-dim-bright cycles take we can figure out how bright it is and from that it's not hard to figure out how far away it is.

Anyway, the relevant bit here is that this paper uses this calibration of the Cepheid Distance Scale to estimate the value of the Hubble constant. They get a value of 74 km/s/Mpc which is pretty close to the accepted value of about 72 (which is well within the uncertainty in this new value). That's a lot different than the 61 km/s/Mpc they got in that Triangulum Galaxy paper.

I don't think you've got to forget what you memorized quite yet, ivy.

Edited by Startraveler, 12 August 2006 - 11:49 PM.


#7    ivytheplant

ivytheplant

    Knows what you're up to

  • Member
  • PipPipPipPipPipPipPipPip
  • 1,509 posts
  • Joined:25 Apr 2006
  • Gender:Female
  • Location:Ivytopia

  • Nothing is impossible, only improbable.

Posted 13 August 2006 - 01:19 AM

Quote


I don't think you've got to forget what you memorized quite yet, ivy.


Oh good, cause honestly, despite ten years in geology, I never did get it down to the point where I didn't have to grab a chart to clarify ages. I'm still trying to get used to Mississippian and Pennsylvanian rather than Carboniferous.

"I reject your reality and substitute my own." - Adam Savage, Mythbusters




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users