Scientists discover ancient galaxies that are still forming starsAugust 19th, 2010 - 6:00 pm ICT by ANI
Washington, Aug 19 (ANI): Astronomers from Texas A&M have discovered a significant fraction of ancient galaxies that are still actively forming stars.
Dr. Kim-Vy Tran and her team used NASA’s Spitzer Space Telescope to discover that a high-redshift cluster known as CLG J02182-05102, shockingly “modern” in its appearance and size despite being observed just 4 billion years after the Big Bang, still produces hundreds to thousands of new stars every year.
The stellar birthrate is higher in the cluster’s center than at the cluster’s edges — the exact opposite of what happens in our local portion of the Universe, where the cores of galaxy clusters are known to be galactic graveyards full of massive elliptical galaxies composed of old stars.
“There are more star-forming galaxies in the field than in the crowded cores of galaxy clusters. However, in our cluster, we find many galaxies with star-formation rates comparable to their cousins in the lower-density field environment,” said Tran.
Exactly why this star power increases as galaxies become more crowded remains a mystery.
Tran thinks the densely populated surroundings could lead to galaxies triggering activity in one another, or that all galaxies were extremely active when the Universe was young.
Astronomers can now focus on understanding why massive assemblies of galaxies transition from very active to passive.
“Our study shows that by looking farther into the distant Universe, we have revealed the missing link between the active galaxies and the quiescent behemoths that live in the local Universe,” Tran added.
Tran will continue to examine these clusters more thoroughly and hopefully to understand why they are still so energetic.
“We will also start looking at several more distant galaxy clusters to see if we find similar behaviour,” she said.
The team’s findings are detailed in their paper, “Reversal of Fortune:
Confirmation of an Increasing Star Formation-Density Relation in a
Cluster at z=1.62.” (ANI)
- "Ancient city of 'modern' galaxies" discovered - May 12, 2010
- Scientists find 'modern' galaxies amongst ancient galaxy clusters - May 13, 2010
- NASA telescopes discover most distant galaxy cluster - Jan 13, 2011
- Scientists find galaxy cluster aged 3bn yrs, but still very young - Mar 10, 2011
- Scientists may have found missing link between young and old galaxies - Jan 11, 2011
- Astronomers spot 3bn-yr-old 'teenager-like, out of control' galaxies - Oct 13, 2010
- Hubble discovers 'most distant and ancient galaxy ever seen' - Jan 27, 2011
- Scientist to make stellar observations aboard Boeing 747 - Dec 02, 2010
- Supermassive black hole discovered in dwarf galaxy - Jan 10, 2011
- Nobel laureate predicts a dark universe - Aug 24, 2012
- Majestic spiral galaxy discovered within the Coma Cluster - Aug 11, 2010
- Galaxies can also be awake or asleep - Jun 22, 2011
- Herschel reveals how much dark matter it takes to form new galaxy - Feb 17, 2011
- Galaxies 'formed much earlier than thought' - Apr 13, 2011
- Hubble telescope spots dwarf galaxies - Nov 11, 2011
Tags: ancient galaxies, behemoths, birthrate, density field, distant galaxy clusters, distant universe, elliptical galaxies, field environment, graveyards, nasa, new stars, power increases, redshift, reversal of fortune, s center, spitzer space telescope, star formation rates, star power, vy tran, young astronomers