Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA's Swift, Fermi Probe Fireworks From a Flaring Gamma-Ray Star

11.02.2009
Astronomers using NASA's Swift satellite and Fermi Gamma-ray Space Telescope are seeing frequent blasts from a stellar remnant 30,000 light-years away. The high-energy fireworks arise from a rare type of neutron star known as a soft-gamma-ray repeater. Such objects unpredictably send out a series of X-ray and gamma-ray flares.

"At times, this remarkable object has erupted with more than a hundred flares in as little as 20 minutes," said Loredana Vetere, who is coordinating the Swift observations at Pennsylvania State University. "The most intense flares emitted more total energy than the sun does in 20 years."

The object, which has long been known as an X-ray source, lies in the southern constellation Norma. During the past two years, astronomers have identified pulsing radio and X-ray signals from it. The object began a series of modest eruptions on Oct. 3, 2008, then settled down. It roared back to life Jan. 22 with an intense episode.

Because of the recent outbursts, astronomers will classify the object as a soft-gamma-ray repeater -- only the sixth known. In 2004, a giant flare from another soft-gamma-ray repeater was so intense it measurably affected Earth's upper atmosphere from 50,000 light-years away.

Scientists think the source is a spinning neutron star, which is the superdense, city-sized remains of an exploded star. Although only about 12 miles across, a neutron star contains more mass than the sun. The object has been cataloged as SGR J1550-5418.

While neutron stars typically possess intense magnetic fields, a subgroup displays fields 1,000 times stronger. These so-called magnetars have the strongest magnetic fields of any known object in the universe. SGR J1550-5418, which rotates once every 2.07 seconds, holds the record for the fastest-spinning magnetar. Astronomers think magnetars power their flares by tapping into the tremendous energy of their magnetic fields.

"The ability of Fermi's gamma-ray burst monitor to resolve the fine structure within these events will help us better understand how magnetars unleash their energy," said Chryssa Kouveliotou, an astrophysicist at NASA's Marshall Space Flight Center in Huntsville, Ala. The object has triggered the instrument more than 95 times since Jan. 22.

Using data from Swift's X-ray telescope, Jules Halpern at Columbia University captured the first "light echoes" ever seen from a soft-gamma-ray repeater. Images acquired when the latest flaring episode began show what appear to be expanding halos around the source. Multiple rings form as X-rays interact with dust clouds at different distances, with closer clouds producing larger rings. Both the rings and their apparent expansion are an illusion caused by the finite speed of light and the longer path the scattered light must travel.

"X-rays from the brightest bursts scatter off of dust clouds between us and the star," Halpern said. "As a result, we don't really know the distance to this object as well as we would like. These images will help us make a more precise measurement and also determine the distance to the dust clouds."

NASA's Wind satellite, the joint NASA-Japan Suzaku mission, and the European Space Agency's INTEGRAL satellite also have detected flares from SGR J1550-5418.

NASA's Goddard Space Flight Center in Greenbelt, Md., manages the Swift satellite. It is being operated in collaboration with partners in the U.S., the United Kingdom, Italy, Germany and Japan. NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle physics observatory developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the U.S.

To see the related images, visit:
http://www.nasa.gov/mission_pages/swift/bursts/gammaray_fireworks.html
For more information about the Swift satellite, visit:
http://www.nasa.gov/swift
For more information about the Fermi mission, visit:
http://www.nasa.gov/fermi

J.D. Harrington | EurekAlert!
Further information:
http://www.nasa.gov
http://www.nasa.gov/mission_pages/swift/bursts/gammaray_fireworks.html

More articles from Physics and Astronomy:

nachricht NASA spacecraft investigate clues in radiation belts
28.03.2017 | NASA/Goddard Space Flight Center

nachricht Researchers create artificial materials atom-by-atom
28.03.2017 | Aalto University

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 Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>