Scientists uncover influence of universe's large-scale structure on galaxy cluster growth

Apr 07, 2010
Figure 1. Image credit: RIKEN

(PhysOrg.com) -- A team headed by researchers at RIKEN (Japan) and the Academia Sinica Institute of Astronomy and Astrophysics has uncovered details explaining the growth of galaxy clusters, the largest gravitationally-bound objects known to exist, offering new clues about the evolution of our universe.

Galaxy clusters are made up of hundreds to thousands of galaxies held together by gravity, yet the visible mass of these galaxies accounts for only a fraction of this attraction. The remainder is attributed to two sources: the intracluster medium (ICM), a superheated plasma detectable via X-ray emissions, and a hypothesized “dark matter” measureable only via its .

The researchers studied the ICM of Abell 1689 using Suzaku, a powerful X-ray astronomical satellite developed in Japan, which they compared with observational data from the U.S. Sloan Digital Sky Survey (SDSS). Suzaku’s high sensitivity enabled them to probe well beyond the range of conventional detectors, to an area at the outskirts of the ICM with a plasma temperature of 23 million degrees, within which they discovered a high-temperature region reaching some 60 million degrees (Fig. 1).

Extending outward from this high-temperature region, the researchers identified a large-scale filamentary structure of galaxies, and determined that it is a shock wave produced by the collision of cold gas from this filament with the galaxy cluster that heats the ICM. Combined with a gravitational lensing study using Japan's Subaru Telescope and the , the results provide a detailed picture, described in the April 9th issue of The Astrophysical Journal, of how cluster growth is affected by the large-scale structure of the surrounding universe.

Explore further: Spectacular supernova's mysteries revealed

add to favorites email to friend print save as pdf

Related Stories

XMM-Newton spots the greatest of great balls of fire

Jun 12, 2006

Thanks to data from ESA's XMM-Newton X-ray satellite, a team of international scientists found a comet-like ball of gas over a thousand million times the mass of the sun hurling through a distant galaxy cluster ...

Survey Reveals Building Block Process For Biggest Galaxies

Apr 12, 2006

A new study of the universe's most massive galaxy clusters shows how mergers play a critical role in their evolution. Astronomers used the twin Gemini Observatory instruments in Hawaii and Chile, and the Hubble Space Telescope ...

Recommended for you

Spectacular supernova's mysteries revealed

Aug 22, 2014

(Phys.org) —New research by a team of UK and European-based astronomers is helping to solve the mystery of what caused a spectacular supernova in a galaxy 11 million light years away, seen earlier this ...

Supernova seen in two lights

Aug 22, 2014

(Phys.org) —The destructive results of a mighty supernova explosion reveal themselves in a delicate blend of infrared and X-ray light, as seen in this image from NASA's Spitzer Space Telescope and Chandra ...

Toothpaste fluorine formed in stars

Aug 21, 2014

The fluorine that is found in products such as toothpaste was likely formed billions of years ago in now dead stars of the same type as our sun. This has been shown by astronomers at Lund University in Sweden, ...

Swirling electrons in the whirlpool galaxy

Aug 20, 2014

The whirlpool galaxy Messier 51 (M51) is seen from a distance of approximately 30 million light years. This galaxy appears almost face-on and displays a beautiful system of spiral arms.

User comments : 0