Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Galaxy halos are produced by orphan stars, findings indicate

25.10.2012
UCI, other researchers discount previous theories about origins of infrared glow
Isolated stars kicked to the edges of space by violent galaxy mergers may be the cause of mysterious infrared light halos observed across the sky, according to UC Irvine and other astronomers.

“Background glow in our sky has been a huge unanswered question,” said UCI physics & astronomy professor Asantha Cooray, lead author of a paper about the discovery in the Oct. 25 issue of the journal Nature. “We have new evidence that this light is from stars that linger between galaxies. Individually, they’re too dim to be seen, but we think we’re seeing their collective blush.”

Cooray and colleagues examined 250 hours of data captured by NASA’s powerful Spitzer Space Telescope from a large swath of sky called the Boötes field, which covers the equivalent of 40 full moons near the constellation of the same name. The large scale allowed the researchers to better analyze the patterns of diffuse light.

“Studying this faint background was one of the core goals of our survey, and we carefully designed the observations in order to directly address this important, challenging question,” said co-author Daniel Stern of NASA’s Jet Propulsion Laboratory in Pasadena.

The team concluded that the infrared glow, while weak, is too strong to be consistent with earlier theories that it’s being emitted by the very first celestial bodies. “The glow is just too bright to be from those ancient, far-off galaxies and stars,” said UCI doctoral student and co-author Joseph Smidt.

Instead, the scientists have a new theory, saying it’s “intracluster” or “intrahalo” starlight. Early in the history of the universe, as galaxies grew, they collided and bulked up in mass. As the crashing galaxies became gravitationally tangled, strips of stars were shredded and tossed into space as leftovers. Galaxies also grow by “swallowing” dwarf neighbors, a messy process that likewise results in stray stars. Cosmologists believe these orphaned stars produce the diffuse, blotchy smatterings of light that make up galaxy halos extending well beyond the outer reaches of galaxies.

Additional research is needed to confirm the theory. But the researchers say it makes sense. “A lightbulb went off when we were reading earlier papers predicting the existence of diffuse stars,” Cooray said. “They explain what we’re seeing with Spitzer.”

Other authors are UCI postdoctoral students Francesco De Bernardis and Yan Gong and undergraduate Christopher Frazer; Peter Eisenhardt of NASA’s Jet Propulsion Laboratory; Matthew Ashby of the Harvard-Smithsonian Center for Astrophysics; Anthony Gonzalez of the University of Florida; Christopher Kochanek and Szymon Koz³owski of The Ohio State University (Koz³owski is also with the Warsaw University Astronomical Observatory); and Edward “Ned” Wright of UCLA. Funding was provided by the National Science Foundation, NASA and JPL.

About the University of California, Irvine: Founded in 1965, UCI is a top-ranked university dedicated to research, scholarship and community service. Led by Chancellor Michael Drake since 2005, UCI is among the most dynamic campuses in the University of California system, with nearly 28,000 undergraduate and graduate students, 1,100 faculty and 9,000 staff. Orange County’s second-largest employer, UCI contributes an annual economic impact of $4 billion. For more UCI news, visit www.today.uci.edu.

News Radio: UCI maintains on campus an ISDN line for conducting interviews with its faculty and experts. Use of this line is available for a fee to radio news programs/stations that wish to interview UCI faculty and experts. Use of the ISDN line is subject to availability and approval by the university.

Janet Wilson | EurekAlert!
Further information:
http://www.uci.edu
http://today.uci.edu/news/2012/10/nr_asantha_121024.php

More articles from Physics and Astronomy:

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>