Subscribe free to our newsletters via your
. 24/7 Space News .




STELLAR CHEMISTRY
Giant Gas Cloud in System NGC 6240
by Staff Writers
Washington DC (SPX) May 02, 2013


Credits: X-ray: NASA/CXC/SAO/E. Nardini et al; Optical: NASA/STScI.

Scientists have used Chandra to make a detailed study of an enormous cloud of hot gas enveloping two large, colliding galaxies. This unusually large reservoir of gas contains as much mass as 10 billion Suns, spans about 300,000 light years, and radiates at a temperature of more than 7 million degrees.

This giant gas cloud, which scientists call a "halo," is located in the system called NGC 6240. Astronomers have long known that NGC 6240 is the site of the merger of two large spiral galaxies similar in size to our own Milky Way.

Each galaxy contains a supermassive black hole at its center. The black holes are spiraling toward one another, and may eventually merge to form a larger black hole.

Another consequence of the collision between the galaxies is that the gas contained in each individual galaxy has been violently stirred up. This caused a baby boom of new stars that has lasted for at least 200 million years. During this burst of stellar birth, some of the most massive stars raced through their evolution and exploded relatively quickly as supernovas.

The scientists involved with this study argue that this rush of supernova explosions dispersed relatively high amounts of important elements such as oxygen, neon, magnesium, and silicon into the hot gas of the newly combined galaxies.

According to the researchers, the data suggest that this enriched gas has slowly expanded into and mixed with cooler gas that was already there.

During the extended baby boom, shorter bursts of star formation have occurred. For example, the most recent burst of star formation lasted for about five million years and occurred about 20 million years ago in Earth's timeframe. However, the authors do not think that the hot gas was produced just by this shorter burst.

What does the future hold for observations of NGC 6240? Most likely the two spiral galaxies will form one young elliptical galaxy over the course of millions of years.

It is unclear, however, how much of the hot gas can be retained by this newly formed galaxy, rather than lost to surrounding space. Regardless, the collision offers the opportunity to witness a relatively nearby version of an event that was common in the early Universe when galaxies were much closer together and merged more often.

In this new composite image of NGC 6240, the X-rays from Chandra that reveal the hot gas cloud are colored purple. These data have been combined with optical data from the Hubble Space Telescope, which shows long tidal tails from the merging galaxies, extending to the right and bottom of the image.

A paper describing these new results on NGC 6240 is available online and appeared in the March 10, 2013 issue of The Astrophysical Journal. The authors in this study were Emanuele Nardini (Harvard-Smithsonian Center for Astrophysics, or CfA, Cambridge, MA and currently at Keele University, UK), Junfeng Wang (CfA and currently at Northwestern University, Evanston, IL), Pepi Fabbiano (CfA), Martin Elvis (CfA), Silvia Pellegrini (University of Bologna, Italy), Guido Risalti (INAF-Osservatorio Astrofisico di Arcetri, Italy and CfA), Margarita Karovska (CfA), and Andreas Zezas (University of Crete, Greece and CfA).

.


Related Links
Chandra X-Ray Observatory
Stellar Chemistry, The Universe And All Within It






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








STELLAR CHEMISTRY
Looking for Life by the Light of Dying Stars
Tel Aviv, Israel (SPX) Apr 30, 2013
Because it has no source of energy, a dead star - known as a white dwarf - will eventually cool down and fade away. But circumstantial evidence suggests that white dwarfs can still support habitable planets, says Prof. Dan Maoz of Tel Aviv University's School of Physics and Astronomy. Now Prof. Maoz and Prof. Avi Loeb, Director of Harvard University's Institute for Theory and Computation ... read more


STELLAR CHEMISTRY
Scientists Use Laser to Find Soviet Moon Rover

Characterizing The Lunar Radiation Environment

Russia rekindles Moon exploration program, intends setting up first human outposts there

Pre-existing mineralogy may survive lunar impacts

STELLAR CHEMISTRY
NASA says Mars rover Opportunity back on the job after standby time

Opportunity in Standby as Commanding Moratorium Ends

Dutch reality show seeks one-way astronauts for Mars

Accurate pointing by Curiosity

STELLAR CHEMISTRY
NASA's Chief Defends Commercial Spaceflight Agreements

NASA Invites the Public to Fly Along with Voyager

Google's Brin keeps spotlight on future technologies

Mysterious water on Jupiter came from comet smash

STELLAR CHEMISTRY
On Course for Shenzhou 10

Yuanwang III, VI depart for space-tracking missions

Shenzhou's Shadow Crew

Shenzhou 10 sent to launch site

STELLAR CHEMISTRY
NASA to pay Russia $424 mln more for lift into space

NASA Extends Crew Flight Contract with Russian Space Agency

Cargo spaceship docks with ISS despite antenna mishap

ISS Communications Test Bed Checks Out; Experiments Begin

STELLAR CHEMISTRY
The Well-Built Italian

O3b Networks' first four satellites arrive for the next Arianespace Soyuz launch

On the record with... Stephane Israel, Arianespace Chairman and CEO

Vega's three-satellite payload is integrated and ready for launch

STELLAR CHEMISTRY
Two New Exoplanets Detected with Kepler, SOPHIE and HARPS-N

Astronomer studies far-off worlds through 'characterization by proxy'

Mysterious Hot Spots Observed In A Cool Red Supergiant

Orbital Selected By NASA for TESS Astrophysics Satellite

STELLAR CHEMISTRY
Astronaut Finds 'Bullet Hole' in ISS Solar Panel

More videogame players moving online: survey

Videogames slow, reverse 'mental decay': study

Older Is Wiser: Study Shows Software Developers' Skills Improve Over Tim




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement