Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Milky Way Gas Cloud Causes Multiple Images of Distant Quasar

For the first time, astronomers have seen the image of a distant quasar split into multiple images by the effects of a cloud of ionized gas in our own Milky Way Galaxy.

Such events were predicted as early as 1970, but the first evidence for one now has come from the National Science Foundation's Very Long Baseline Array (VLBA) radio telescope system.

Artist's Diagram of the refraction event (not drawn to scale), showing how radio waves from the distant quasar jet are bent by a gas cloud in our own Galaxy, creating multiple images seen with the Very Long Baseline Array.
Credit: Bill Saxton, NRAO/AUI/NSF

The scientists observed the quasar 2023+335, nearly 3 billion light-years from Earth, as part of a long-term study of ongoing changes in some 300 quasars. When they examined a series of images of 2023+335, they noted dramatic differences. The differences, they said, are caused by the radio waves from the quasar being bent as they pass through the Milky Way gas cloud, which moved through our line of sight to the quasar.

"This event, obviously rare, gives us a new way to learn some of the properties of the turbulent gas that makes up a significant part of our Galaxy," said Matt Lister, of Purdue University.

The scientists added 2023+335 to their list of observing targets in 2008. Their targets are quasars and other galaxies with supermassive black holes at their cores. The gravitational energy of the black holes powers "jets" of material propelled to nearly the speed of light. The quasar 2023+335 initially showed a typical structure for such an object, with a bright core and a jet. In 2009, however, the object's appearance changed significantly, showing what looked like a line of bright, new radio-emitting spots.

"We've never seen this type of behavior before, either among the hundreds of quasars in our own observing program or among those observed in other studies," Lister said.

The multiple-imaging event came as other telescopes detected variations in the radio brightness of the quasar, caused, the astronomers said, by scattering of the waves.

The scientists' analysis indicates that the quasar's radio waves were bent by a turbulent cloud of charged gas nearly 5,000 light-years from Earth in the direction of the constellation Cygnus. The cloud's size is roughly comparable to the distance between the Sun and Mercury, and the cloud is moving through space at about 56 kilometers per second.

Monitoring of 2023+335 over time may yield more such events, the scientists said, allowing them to learn additional details both about the process by which the waves are scattered and about the gas that does the scattering. Other quasars that are seen through similar regions of the Milky Way also may show this behavior.

The monitoring program that yielded this discovery is called MOJAVE (Monitoring Of Jets in Active galactic nuclei with VLBA Experiments), run by an international team of scientists led by Lister. The analysis of this rare event was spearheaded by Alexander Pushkarev of the Max Planck Institute for Radioastronomy in Germany. The researchers recently published their results in the journal Astronomy and Astrophysics.

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

Dave Finley | EurekAlert!
Further information:

More articles from Physics and Astronomy:

nachricht Scientists discover particles similar to Majorana fermions
25.10.2016 | Chinese Academy of Sciences Headquarters

nachricht Light-driven atomic rotations excite magnetic waves
24.10.2016 | Max-Planck-Institut für Struktur und Dynamik der Materie

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: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Ice shelf vibrations cause unusual waves in Antarctic atmosphere

25.10.2016 | Earth Sciences

Fluorescent holography: Upending the world of biological imaging

25.10.2016 | Power and Electrical Engineering

Etching Microstructures with Lasers

25.10.2016 | Process Engineering

More VideoLinks >>>