Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Supernova 1987A: Fast Forward to the Past

18.08.2005


Recent Chandra observations have revealed new details about the fiery ring surrounding the stellar explosion that produced Supernova 1987A. The data give insight into the behavior of the doomed star in the years before it exploded, and indicate that the predicted spectacular brightening of the circumstellar ring has begun.


Credit: X-ray: NASA/CXC/U.Colorado/S.Zhekov et al.; Optical: NASA/STScI/CfA/P.Challis



The supernova occurred in the Large Magellanic Cloud, a galaxy only 160,000 light years from Earth. The outburst was visible to the naked eye, and is the brightest known supernova in almost 400 years. The site of the explosion was traced to the location of a blue supergiant star called Sanduleak -69º 202 (SK -69 for short) that had a mass estimated at approximately 20 Suns.

Subsequent optical, ultraviolet and X-ray observations have enabled astronomers to piece together the following scenario for SK -69: about ten million years ago the star formed out of a dark, dense, cloud of dust and gas; roughly a million years ago, the star lost most of its outer layers in a slowly moving stellar wind that formed a vast cloud of gas around it; before the star exploded, a high-speed wind blowing off its hot surface carved out a cavity in the cool gas cloud.


The intense flash of ultraviolet light from the supernova illuminated the edge of this cavity to produce the bright ring seen by the Hubble Space Telescope. In the meantime the supernova explosion sent a shock wave rumbling through the cavity.

In 1999, Chandra imaged this shock wave, and astronomers have waited expectantly for the shock wave to hit the edge of the cavity, where it would encounter the much denser gas deposited by the red supergiant wind, and produce a dramatic increase in X-radiation. The latest data from Chandra and the Hubble Space Telescope indicate that this much-anticipated event has begun.

Optical hot-spots now encircle the ring like a necklace of incandescent diamonds (image on right). The Chandra image (left) reveals multimillion-degree gas at the location of the optical hot-spots.

X-ray spectra obtained with Chandra provide evidence that the optical hot-spots and the X-ray producing gas are due to a collision of the outward-moving supernova shock wave with dense fingers of cool gas protruding inward from the circumstellar ring (see illustration). These fingers were produced long ago by the interaction of the high-speed wind with the dense circumstellar cloud.

The dense fingers and the visible circumstellar ring represent only the inner edge of a much greater, unknown amount of matter ejected long ago by SK -69. As the shock wave moves into the dense cloud, ultraviolet and X-radiation from the shock wave will heat much more of the circumstellar gas.

Then, as remarked by Richard McCray, one of the scientists involved in the Chandra research, "Supernova 1987A will be illuminating its own past."

Fast Facts for Supernova 1987A:
Credit X-ray: NASA/CXC/U.Colorado/S.Zhekov et al.; Optical: NASA/STScI/CfA/P.Challis
Scale Each panel is 2.4 arcsec per side.
Category Supernovas & Supernova Remnants
Coordinates (J2000) RA 05h 35m 28.30s | Dec -69º 16’ 11.10
Constellation Dorado
Observation Dates January 9, 2005
Observation Time 30 hours
Obs. IDs 5579
Color Code Intensity
Instrument ACIS
Also Known As SN 1987A
References S. A. Zhekov, R. McCRay, K. Borkowski, D. Burrows, and S. Park, "Chandra Observations of Shock Kinematics in Supernova Remnant 1987A" , Astrophysical Journal Letters, Volume 628, pp. L127-L130. 2005 (See also astro-ph/0506443)
Distance Estimate About 160,000 light years
Release Date August 17, 2005

Megan Watzke | EurekAlert!
Further information:
http://chandra.harvard.edu/photo/2005/sn87a/
http://www.cfa.harvard.edu

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 >>>