Featured Research

from universities, journals, and other organizations

Far-Flung Galaxy Clusters May Reveal Fate Of Universe

Date:
August 28, 1998
Source:
Space Telescope Science Institute
Summary:
A survey of galaxy clusters by NASA's Hubble Space Telescope has found what could be some of the most distant clusters ever seen. If the distances and masses of the clusters are confirmed by ground-based telescopes, the survey may hold clues to how galaxies quickly formed into massive large-scale structures after the Big Bang, and what that may mean for the eventual fate of the universe.

A survey of galaxy clusters by NASA's Hubble Space Telescope has found what could be some of the most distant clusters ever seen. If the distances and masses of the clusters are confirmed by ground-based telescopes, the survey may hold clues to how galaxies quickly formed into massive large-scale structures after the Big Bang, and what that may mean for the eventual fate of the universe.

According to theoretical models, if the clusters turn out to be massive and very distant, it could imply that the cosmos does not contain enough matter for gravity to stop the expansion of the universe. These models predict that such a low-density universe would have built most of its galaxy clusters long ago.

About 10 to 20 of the farthest clusters in the Hubble survey may be over seven billion light years away, which means that the clusters, and their populations of tens or perhaps hundreds of galaxies each, were fully assembled early in the history of the universe.

Present distance estimates are based on the colors of the galaxies in each cluster. The redder the overall cluster appears, the more distant it is, an assumption based on the apparent reddening of light -- known as red shift -- as stars and galaxies move away from us at high speeds. The distances can be more accurately measured using a spectrograph attached to a ground-based telescope.

The Hubble survey contains 92 new clusters uncovered during a six-year sky survey known as the Medium Deep Survey, led by a team of astronomers now at Carnegie Mellon University, Pittsburgh, PA.

The project has been led by Professor Richard Griffiths and senior scientist Dr. Kavan Ratnatunga. The catalog samples an area of the sky that is small, but scattered over 300 random directions.

The clusters were found using an automated procedure developed by the Carnegie Mellon team. They first identified large elliptical galaxies in random fields taken by Hubble. Next, an automated procedure was used to search statistically for an over-abundance of galaxies around the large elliptical galaxies. The assumption is that the excess galaxies all belong to the same cluster. This procedure helped to discriminate clusters against the field galaxy population which is smoothly distributed across the sky.

Major new telescopes must be used to study these clusters to measure their distances. The whole HST catalog of galaxies can be searched on the web at: http://astro.phys.cmu.edu/mds/

The Hubble observations will be published in the Astronomical Journal. The research team members are: E. J. Ostrander; K. U. Ratnatunga; and R. E. Griffiths, Department of Physics, Carnegie Mellon University. The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) for NASA, under contract with the Goddard Space Flight Center, Greenbelt, MD. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA).- end -EDITOR'S NOTE: Images from Hubble's Medium Deep Field catalog are available on the Internet at: http://oposite.stsci.edu/latest


Story Source:

The above story is based on materials provided by Space Telescope Science Institute. Note: Materials may be edited for content and length.


Cite This Page:

Space Telescope Science Institute. "Far-Flung Galaxy Clusters May Reveal Fate Of Universe." ScienceDaily. ScienceDaily, 28 August 1998. <www.sciencedaily.com/releases/1998/08/980828074251.htm>.
Space Telescope Science Institute. (1998, August 28). Far-Flung Galaxy Clusters May Reveal Fate Of Universe. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/1998/08/980828074251.htm
Space Telescope Science Institute. "Far-Flung Galaxy Clusters May Reveal Fate Of Universe." ScienceDaily. www.sciencedaily.com/releases/1998/08/980828074251.htm (accessed July 22, 2014).

Share This




More Space & Time News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Cargo Craft Undocks from Space Station

Raw: Cargo Craft Undocks from Space Station

AP (July 22, 2014) A Russian Soyuz cargo-carrying spacecraft undocked from the International Space Station on Monday. The craft is due to undergo about ten days of engineering tests before it burns up in the Earth's atmosphere. (July 22) Video provided by AP
Powered by NewsLook.com
NASA Ceremony Honors Moon Walker Neil Armstrong

NASA Ceremony Honors Moon Walker Neil Armstrong

AP (July 21, 2014) NASA honored one of its most famous astronauts Monday by renaming a historic building at the Kennedy Space Center in Florida. It now bears the name of Neil Armstrong, the first man to walk on the moon. (July 21) Video provided by AP
Powered by NewsLook.com
Neil Armstrong's Post-Apollo 11 Life

Neil Armstrong's Post-Apollo 11 Life

Newsy (July 19, 2014) Neil Armstrong gained international fame after becoming the first man to walk on the moon in 1969. But what was his life like after the historic trip? Video provided by Newsy
Powered by NewsLook.com
This Week @ NASA, July 18, 2014

This Week @ NASA, July 18, 2014

NASA (July 18, 2014) Apollo 11 yesterday, Next Giant Leap tomorrow, Science instruments for Europa mission, and more... Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins