Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New research dives into details of supernova

25.03.2008
Astronomers have made the best determination of the power of a supernova explosion long after it was visible from Earth. This technique, using X-ray and optical observations, may help reveal the details of how some stars come to a cataclysmic death.

Using data from NASA’s Chandra X-ray Observatory, the Gemini Observatory and ESA’s XMM-Newton Observatory, two teams of international researchers, including Lawrence Livermore National Laboratory scientists Kem Cook and Sergei Nikolaev, determined that a supernova that occurred about 400 years ago was unusually bright and energetic.

By observing the remnant of a supernova and a light echo from the initial explosion, the teams have established the validity of a new method for studying a type of supernova that produces most of the iron in the universe. The two teams of researchers studied the supernova remnant and the supernova light echo that are located in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light years from Earth

This is the first time two methods – X-ray observations of the supernova remnant and optical observations of the expanding light echoes – have been combined to study a supernova. Until now, scientists could only estimate the power of explosions from the light seen soon after a star exploded, or from remnants that are several hundred years old, but not from both.

And the results could have implications in identifying similar incidents in the Milky Way.

“Classifying outbursts associated with centuries-old remnants is likely to be successful in providing new constraints on additional LMC supernovae as well as their historical counterparts in our own galaxy,” Cook said.

In 2004, scientists used Chandra to determine that a supernova remnant, known as SNR 0509-67.5 in the LMC, was a Type Ia supernova, which is caused by a white dwarf star in a binary system that reaches a critical mass and explodes.

In the new optical study, an estimate of the explosion’s power came from studying the original light of the explosion as it travels through space. Just as sound bounces off walls of a canyon, light waves create an echo by bouncing off dust clouds in space. The light from these echoes travels a longer path than the light that travels straight toward us, and so can be seen hundreds of years after the original explosion.

"People didn’t have advanced telescopes to study supernovas when they went off hundreds of years ago," said Armin Rest of Harvard University, who led the light echo observations. "But we’ve done the next best thing by looking around the site of the explosion and constructing an action replay of it."

First seen by the Cerro-Tololo Inter-American Observatory in Chile, the light echoes were observed in greater detail by Gemini Observatory in Chile. The optical spectra of the light echo were used to confirm the supernova was a Type Ia and to unambiguously determine the particular class of explosion and its energy.

The Chandra and XMM data were then independently used to calculate the amount of energy involved in the original explosion, using analysis of the supernova remnant and state-of-the-art explosion models. The conclusion was that the explosion was an especially energetic and bright variety of Type Ia supernova, providing strong evidence that the detailed explosion models are accurate.

Cook and Nikolaev are active members of the SuperMACHO project, a five-year microlensing survey of the LMC. The light echo research evolved out of the serendipitous discovery of light echos in SuperMACHO.

Both methods estimated a similar time since the explosion of about 400 years. An extra constraint on the age comes from the lack of recorded historical evidence for a recent supernova in the LMC. Because this star appears in the Southern Hemisphere, it likely would have been seen by navigators who noted similarly bright celestial events, if it had occurred less than about 400 years ago.

Because a Type Ia supernova brightness can be determined from its spectrum or the way its apparent brightness fades, Type Ia supernovae are important tools to study the expansion of the universe and the nature of dark energy.

“This is the first time that spectra were obtained of an ancient supernova, and they were good enough to allow us to identify the supernova as belonging to a particularly bright class of type Ia supernovae,” Cook said.

This work also is being extended to other supernova remnants and light echoes.

These results appear in two recently accepted papers in The Astrophysical Journal. The first discusses the spectrum obtained by Gemini, led by Rest. The second, with Carlos Badenes of Princeton as first author, details the Chandra observations of SNR 0509-67.5.

Other institutions involved in the research include Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Harvard-Smithsonian Center for Astrophysics, Gemini Observatory, McMaster University, Texas A&M University, Ohio State University, Washington University, University of Washington, Las Campanas Observatory, Pontificia Universidad Católica de Chile, Universidad de Chile and UC Berkeley.

Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.

Anne Stark | EurekAlert!
Further information:
http://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-03-06.html

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>