Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A scientific first: A Supernova Explosion is Observed in Real Time

23.05.2008
As members of a team analyzing data from the first real-time observation of a supernova explosion, Weizmann Institute scientists are finding confirmation for their model of the process and helping to solve unanswered questions.

An ordinary observation with NASA's Swift research satellite recently led to the first real-time sighting of a star in the process of exploding. Astronomers have surveyed thousands of these supernova explosions in the past, but their observations have always begun some time after the main event is underway. The information gained from catching a supernova at the very onset is already being hailed as the 'Rosetta Stone' of star explosion, and it is helping scientists to form a detailed picture of the processes involved.

A typical supernova is preceded by the burn-out of a massive star. When the nuclear fuel at its core runs out, the star collapses under its own weight. The resulting body, now known as a neutron star, is so dense that one teaspoonful of its core material weighs as much as all the humans on earth. This extreme compression is followed by a rebound, creating a shock wave that bounces off the surface of the newly-formed neutron star and rips through its outer, gaseous layers. These layers are ejected, flying off the surface in rapidly expanding shells.

For the last four decades, astronomers have theorized that the explosion is preceded by a burst of x-ray radiation that lasts for several minutes. For the first time, that burst was actually seen - all previous observations had taken place when the star was already an expanding shell of debris, days or even weeks after the explosions' start. Both luck and the Swift satellite's unique design played a role in the discovery. In January of this year, Drs. Alicia Soderberg and Edo Berger of Princeton University, USA, were using the satellite, which measures gamma rays, X rays and ultraviolet light, to observe another supernova in a spiral galaxy in the Lynx constellation, 90 million light-years from Earth. At 9:33 EST, they spotted an extremely bright five-minute X-ray burst and realized it was coming from another location within the same galaxy.

The Princeton scientists immediately assembled a team of 15 research groups around the world to investigate, including Prof. Eli Waxman and Dr. Avishay Gal-Yam of the Weizmann Institute's Physics Faculty. Gal-Yam performed measurements and calculations that enabled the scientific team to cancel out the various disturbances that affect astronomical data, such as radiation-absorbing interstellar dust, which skews observed measurements. The shock-wave eruption and X-ray generation of this supernova explosion went exactly according to the theoretical model that Waxman and Prof. Peter Meszaros of Penn State University had developed earlier. The data showed that the explosion - known as supernova 2008D - is a relatively common type of supernova, and not a rare supernova involving jets of gamma ray radiation.

Already, the observation has provided scientists with valuable new information on supernovae, including the dimensions of the exploding star, the structure of its envelope and the properties of the shock wave that hurls off the star's outer envelope. As they continue to analyze the data, the scientists believe it may help them to solve some of the outstanding puzzles surrounding these types of explosion. For instance, according to mathematical calculations of the forces involved in neutron star collapse, the bouncing shock wave should stall out before it manages to eject the stellar envelope. Clearly, this is not what happens in nature, but clues found in the Swift observations may help researchers to correct the model.

Now that they have observed a supernova from the pre-explosion stage, the scientists are not only gaining a better understanding of the little-understood processes that make these stars explode; they hope their knowledge of the x-ray emissions will enable them to catch more stars that are right on the brink of becoming supernovae.

Prof. Eli Waxman is Head of the Benoziyo Center for Astrophysics and the Albert Einstein Minerva Center for Theoretical Physics.

Dr. Avishai Gal-Yam's research is supported by the Nella and Leon Benoziyo Center for Astrophysics and the William Z. and Eda Bess Novick Young Scientist Fund.

The Weizmann Institute of Science in Rehovot, Israel, is one of the world's top-ranking multidisciplinary research institutions. Noted for its wide-ranging exploration of the natural and exact sciences, the Institute is home to 2,600 scientists, students, technicians and supporting staff. Institute research efforts include the search for new ways of fighting disease and hunger, examining leading questions in mathematics and computer science, probing the physics of matter and the universe, creating novel materials and developing new strategies for protecting the environment.

Weizmann Institute news releases are posted on the World Wide Web at
http://wis-wander.weizmann.ac.il, and are also available at http://www.eurekalert.org.

Batya Greenman | idw
Further information:
http://www.weizmann.ac.il/
http://wis-wander.weizmann.ac.il/site/en/weizman.asp?pi=371&doc_id=5126

More articles from Physics and Astronomy:

nachricht Appreciating the classical elegance of time crystals
20.09.2019 | ETH Zurich Department of Physics

nachricht 'Nanochains' could increase battery capacity, cut charging time
20.09.2019 | Purdue 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: 'Nanochains' could increase battery capacity, cut charging time

How long the battery of your phone or computer lasts depends on how many lithium ions can be stored in the battery's negative electrode material. If the battery runs out of these ions, it can't generate an electrical current to run a device and ultimately fails.

Materials with a higher lithium ion storage capacity are either too heavy or the wrong shape to replace graphite, the electrode material currently used in...

Im Focus: Stevens team closes in on 'holy grail' of room temperature quantum computing chips

Photons interact on chip-based system with unprecedented efficiency

To process information, photons must interact. However, these tiny packets of light want nothing to do with each other, each passing by without altering the...

Im Focus: Happy hour for time-resolved crystallography

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.

The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.

Im Focus: Modular OLED light strips

At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.

Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...

Im Focus: Tomorrow´s coolants of choice

Scientists assess the potential of magnetic-cooling materials

Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

 
Latest News

Quality control in immune communication: Chaperones detect immature signaling molecules in the immune system

20.09.2019 | Life Sciences

Moderately Common Plants Show Highest Relative Losses

20.09.2019 | Life Sciences

The Fluid Fingerprint of Hurricanes

20.09.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>