Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The origin of supernovae confirmed

23.03.2009
Where do supernovae come from? Astronomers have long believed they were exploding stars, but by analysing a series of images, researchers from the Dark Cosmology Centre at the Niels Bohr Institute, University of Copenhagen and from Queens University, Belfast have proven that two dying red supergiant stars produced supernovae. The results are published in the prestigious scientific journal, Science.

A star is a large ball of hot gas and in its incredibly hot interior hydrogen atoms combine to form helium, which subsequently forms carbon, other heavier elements and finally iron. When all the atoms in the centre have turned to iron the fuel is depleted and the star dies. When very large and massive stars, that are at least about eight times as massive as our sun, die, they explode as supernovae.

Enormous swollen stars

But some massive stars become red supergiant stars first, which is an intermediate phase where, after the fuel in the centre is used up, energy is still produced in shells surrounding the now dead core. In this phase, the star swells up to an enormous size, approximately 1500 times larger than the sun, and emits as much light as a hundred thousand suns. But there has been doubt over whether red supergiants explode as supernovae.

Using images from the Hubble Space Telescope and the Gemini Observatory, Justyn R. Maund, astrophysicist at the Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen and astrophysicist Stephen J. Smartt, Queens University Belfast, have observed two stars that exploded as supernovae. By analysing archival images of the same section of the sky from long before the explosions, the researchers could see which stars might have gone supernova. But picking out individual stars in the distant universe is difficult, and pinpointing exactly which star it was that exploded is a huge challenge.

Stars became supernovae

A supernova is visible in the sky for some time after its explosion before its giant dust- and gas clouds are blown clear. The researchers can then observe the region around the position of the supernova several years after the supernova explosion and can then see exactly which star has disappeared.

For one of the supernovae, SN1993J (which exploded in 1993) they found that a red supergiant no longer exists, but that its neighboring star remained. In addition, they found that the red supergiant that was postulated to have caused the supernova SN2003gd has also disappeared. This simple but very time intensive method, establishes that it was these two red supergiant stars that produced the supernovae 2003J and 2003gd, and confirms that red supergiant stars create type II supernovae.

Maund and Smartt have found the missing link between red supergiant stars and their supernovae, giving astronomers a greater understanding of how massive stars die. Stellar death is a process crucial for understanding the origin of the chemical elements in the Universe, a precursor necessary ultimately to the formation of planets and life.

Gertie Skaarup | EurekAlert!
Further information:
http://www.nbi.dk
http://www.sciencemag.org/cgi/content/short/1170198

More articles from Physics and Astronomy:

nachricht NASA's James Webb Space Telescope completes final cryogenic testing
21.11.2017 | NASA/Goddard Space Flight Center

nachricht Previous evidence of water on mars now identified as grainflows
21.11.2017 | US Geological Survey

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: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

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,...

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

Previous evidence of water on mars now identified as grainflows

21.11.2017 | Physics and Astronomy

NASA's James Webb Space Telescope completes final cryogenic testing

21.11.2017 | Physics and Astronomy

New catalyst controls activation of a carbon-hydrogen bond

21.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>