Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Two Galaxies for the Price of One

03.12.2013
Surprising Image Reveals New Tool to Study Magnetic Fields of Galaxies

An international group of astronomers, including Marita Krause and Rainer Beck from Max-Planck-Institut für Radioastronomie (MPIfR) in Bonn, has found a surprising and useful new probe of galactic magnetic fields. While studying gas halos around nearby galaxies, they were surprised when detailed studies with the Karl G. Jansky Very Large Array (VLA) showed that one of their subjects is not a single galaxy, but rather two, nearly perfectly superimposed on the sky to masquerade as one. The discovery allowed them to use the alignment to learn otherwise-unobtainable facts about the nearer galaxy.


The edge-on spiral galaxy UGC 10288 (horizontal) appeared to be a single object in previous radio telescope observations. However, new, detailed radio data (cyan in this image) from the NRAO's VLA reveals that the large perpendicular (vertical) extension really is a distant background galaxy with radio jets. The foreground image of UGC 10288 includes data from optical, infrared and radio telescopes. While radio data are blue, infrared observations from NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) are yellow and orange, respectively. Optical data from the Sloan Digital Sky Survey are purplish blue and show starlight; and optical data from the Kitt Peak National Observatory are rose and show heated gas.

© Jayanne English (University of Manitoba, Kanada), Judith Irwin (Queen's University, Kanada), Richard Rand, University of New Mexico, Albuquerque, and members of CHANG-ES consortium, NRAO VLA, NASA/JPL-Caltech WISE & Spitzer, NOAO, and SDSS.


This image of UGC 10288, the foreground spiral galaxy, includes data from NASA's WISE (far-infrared; orange) and Spitzer (near-infrared; yellow) space observatories, the Kitt Peak National Observatory's 0.9m telescope (ionized hydrogen; rose), and the Sloan Digital Sky Survey (optical; purplish-blue), and NRAO's VLA (radio; cyan).

© see Fig. 1

As part of a study of 35 galaxies, the astronomers observed one called UGC 10288, a spiral galaxy more than 100 million light-years distant that appears edge-on as seen from Earth. Their multiple VLA observations in 2011 and 2012 produced the best radio-telescope images of that galaxy ever made. The detailed images surprisingly revealed a more-distant galaxy, with strong radio emission, almost directly behind UGC 10288. In previous images, the two galaxies had been blended together. It is probably the first detection of an alignment of a foreground galaxy with such a strongly- emitting background galaxy with extended jets. The background galaxy is much further away, in a distance of nearly 7 billion light-years from Earth.

"This changed the picture, quite literally," says Judith Irwin, of Queen's University in Ontario, Canada. "It changed our understanding of the characteristics of UGC 10288, but also gave us an unexpected new tool for learning more about that galaxy."

The first insight gleaned from the improved images was that UGC 10288 is not forming stars as rapidly as the astronomers first thought. This is because much of the radio emission in the previous, blended images came from the background galaxy.

The new images also showed that the gas in the galaxy's "outskirts," high above its spiral disk does not form a smooth halo-like envelope as result of an extremely low star formation rate.

The background galaxy, and the fact that it is aligned with its radio jets perpendicular to UGC 10288's disk, provides a valuable means of studying the nearer galaxy. "We can use the radio waves from the background galaxy, coming through the nearer one, as a way to measure the properties of the nearer galaxy," says Jayanne English, of the University of Manitoba.

“The use of the more distant galaxy as a background candle has given us the opportunity of magnetic-field measurements in different areas of UGC 10288,” explains Marita Krause from the Max-Planck-Institut für Radioastronomie in Bonn, Germany. “Since the background galaxy is vertically orientated, we can study the magnetic field of the foreground galaxy from the disk up to regions high above.”

The researchers could measure the magnetic field via the effect of Faraday rotation which rotates the polarization plane of the radio emission of the background galaxy within the foreground galaxy.

"Ironically, the radio brightness of UGC 10288 alone is too weak to be included in the original sample, had it not been boosted by the unresolved background galaxy in earlier images," concludes Rainer Beck, also from Max-Planck-Institut für Radioastronomie. “We would have missed an excellent opportunity for magnetic field studies via extended background sources.”

Marita Krause and Rainer Beck, both from Max-Planck-Institut für Radioastronomie (MPIfR), Bonn, Germany, worked with an international team of astronomers from North America, Europe, and India who are part of the Continuum Halos in Nearby Galaxies - an EVLA Survey (CHANG-ES) consortium, led by Judith Irwin. The scientists report their findings in the December issue of the Astronomical Journal.

The National Radio Astronomy Observatory (NRAO) is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Contact

Dr. Marita Krause
Phone:+49 228 525-312
Email:mkrause@mpifr-bonn.mpg.de
Max-Planck-Institut für Radioastronomie, Bonn
Dr. Rainer Beck
Phone:+49 228 525-323
Email:rbeck@mpifr-bonn.mpg.de
Max-Planck-Institut für Radioastronomie, Bonn
Dr. Norbert Junkes
Presse- und Öffentlichkeitsarbeit
Phone:+49 228 525-399
Email:njunkes@mpifr-bonn.mpg.de
Max-Planck-Institut für Radioastronomie, Bonn
Original Paper
CHANG-ES III: UGC10288 – An Edge-on Galaxy with a Background Double-lobed Radio Source

Judith Irwin, Marita Krause, Jayanne English, Rainer Beck, Eric Murphy, Theresa Wiegert, George Heald, Rene Walterbos, Richard J. Rand, and Troy Porter, 2013, Astronomical Journal 146, 164 (eprint arXiv:1311.3894)

Dr. Norbert Junkes | Max-Planck-Institut
Further information:
http://www.mpifr-bonn.mpg.de/pressreleases/2013/12

More articles from Physics and Astronomy:

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

nachricht Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz

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: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>