Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Wild, Hidden Cousin of SN 1987A - Powerful nearby supernova caught by web of telescopes

25.09.2008
The supernova, called SN 1996cr, was first singled out in 2001 by Franz Bauer. Bauer noticed a bright, variable source in the Circinus spiral galaxy, using NASA's Chandra X-ray Observatory. Although the source displayed some exceptional properties Bauer and his Penn State colleagues could not identify its nature confidently at the time.

It was not until years later that Bauer and his team were able to confirm that this object was a supernova. Clues from a spectrum obtained by ESO’s Very Large Telescope led the team to start the real detective work of searching through data from 18 different telescopes, both ground- and space-based, nearly all of which existed. Because this object was found in an interesting nearby galaxy, the public archives of these telescopes contained abundant observations.

The data show that SN 1996cr is among the brightest supernovae ever seen in radio and X-rays. It also bears many striking similarities to the famous supernova SN 1987A, which occurred in a neighbouring galaxy only 160 000 light-years from Earth.

“This supernova appears to be a wild cousin of SN 1987A,” says Bauer. “The two look alike in many ways, except this newer supernova is intrinsically a thousand times brighter in radio and X-rays.”

Visible-light images from the archives of the Anglo-Australian Telescope in Australia show that SN 1996cr exploded sometime between 28 February 1995 and 15 March 1996, but it is the only one of the five nearest supernovae of the last 25 years that was not seen shortly after the explosion.

Other major X-ray observatories in orbit like ROSAT and ASCA did not detect SN 1996cr, but since it was first detected by Chandra in 2001 it has become steadily brighter. Previously, SN 1987A was the only known supernova with an X-ray output that increased over time.

“It’s a bit of a coup to find SN 1996cr like this, and we could never have nailed it without the serendipitous data taken by all of these telescopes. We've truly entered a new era of ‘internet astronomy’,” said Bauer.

The combined data, in conjunction with theoretical work, have led the team to develop a model for the explosion. Before the parent star exploded, it cleared out a large cavity in the surrounding gas, either via a strong wind or from an outburst from the star late in its life. So the blast wave from the explosion itself could expand relatively unimpeded into this cavity. Once the blast wave hit the dense material surrounding SN1996cr, the impact caused the system to glow brightly in X-ray and radio emission. The X-ray and radio emission from SN 1987A is probably fainter because the surrounding material is less compact.

Astronomers think that both SN 1987A and SN 1996cr show evidence for these pre-explosion clear-outs by a star doomed to explode. Having two nearby examples suggests that this type of activity could be relatively common during the death of massive stars.

“Not only does our work suggest that SN 1987A isn’t as unusual as previously thought, but it also teaches us more about the tremendous upheavals that massive stars can undergo over their lifetimes,” said co-author Vikram Dwarkadas of the University of Chicago.

Henri Boffin | alfa
Further information:
http://www.eso.org/public/outreach/press-rel/pr-2008/pr-32-08.html

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 >>>