Supernova in real time, for the first time

[rangerover777]

Check this out :

http://www.nasa.gov/centers/goddard/new ... rnova.html

[MGmirkin]

Astronomers have previously observed thousands of stellar explosions, known as supernovae, but they have always seen them after the fireworks were well underway.

"For years we have dreamed of seeing a star just as it was exploding, but actually finding one is a once in a lifetime event," says team leader Alicia Soderberg, a Hubble and Carnegie-Princeton Fellow at Princeton University in Princeton, N.J. "This newly born supernova is going to be the Rosetta stone of supernova studies for years to come."

[...]

... until this discovery, astronomers have never observed this signal. Instead, they have observed supernovae brightening days or weeks later, when the expanding shell of debris is energized by the decay of radioactive elements forged in the explosion. "Seeing the shock break-out in X-rays can give a direct view of the exploding star in the last minutes of its life and also provide a signpost to which astronomers can quickly point their telescopes to watch the explosion unfold," says Edo Berger, a Carnegie-Princeton Fellow at Princeton University.

[...]

On January 9, 2008, Soderberg and Berger were using Swift to observe a supernova known as SN 2007uy in the spiral galaxy NGC 2770, located 90 million light-years from Earth in the constellation Lynx. At 9:33 a.m. EST they spotted an extremely bright 5-minute X-ray outburst in NGC 2770. They quickly recognized that the X-rays were coming from another location in the same galaxy.

[...]

Although astronomers were lucky that Swift was observing NGC 2770 just at the moment when SN 2008D’s shock wave was blowing up the star, Swift is well equipped to study such an event because of its multiple instruments observing in gamma rays, X-rays, and ultraviolet light. "It was a gift of nature for Swift to be observing that patch of sky when the supernova exploded. But thanks to Swift's flexibility, we have been able to trace its evolution in detail every day since," says Swift lead scientist Neil Gehrels of NASA’s Goddard Space Flight Center in Greenbelt, Md.

Due to the significance of the X-ray outburst, Soderberg immediately mounted an international observing campaign to study SN 2008D. Observations were made with major telescopes such as the Hubble Space Telescope, the Chandra X-ray Observatory, the Very Large Array in New Mexico, the Gemini North telescope in Hawaii, the Keck I telescope in Hawaii, the 200-inch and 60-inch telescopes at the Palomar Observatory in California, and the 3.5-meter telescope at the Apache Point Observatory in New Mexico.

[...]

Significantly, radio and X-ray observations found no evidence that a jet played a role in the explosion, ruling out a rare type of stellar explosion known as a gamma-ray burst.

Yup, looks cool. Should be interesting to see what all they discover about it...

Cheers,
~Michael Gmirkin

[junglelord]

Same information, from the physics news press release web page.

Number 865 #1, May 29, 2008 by Phil Schewe
Exploding Star Caught on Tape

Call it fantastic timing. Early this year, a group of astronomers led by Princeton University's Alicia Soderberg were using NASA's Swift satellite to observe a new supernova-one of those spectacular explosions that mark the end of a massive star's life. This supernova was in a galaxy some 100 million light years away. It was relatively unremarkable, Soderberg admits. But then something extraordinary happened. On January 9, in what some astronomers are calling a remarkable stroke of good luck, another star in their field of view went supernova. "We actually watched the star explode," says Soderberg, who was in Michigan, talking to an audience of fellow scientists about her research when the call about the supernova came from her colleague. This set off a week of scrambling to get astronomers across the globe to point telescopes at the supernova to confirm and better study the phenomenon.

Astronomers have never before seen a star at the first moments of its explosive death. Usually, astronomers miss the earliest flash of a supernova because the explosion is only visible to orbiting x-ray detectors on platforms like Swift. In the 22 May 2008 issue of Nature, Soderberg and her colleagues describe how the supernova's initial burst lasted a few minutes and then faded away. Its power was remarkable. In 10 minutes, the exploding star expelled the about the same amount of energy as the sun puts out in 82,000 years.

"It's incredibly serendipitous," says Harvard astrophysics professor Josh Grindlay, a supernova expert who was not involved in the research. "This almost certainly provides a whole new way of detecting supernovae." Though astronomers have known about supernovas for hundreds of years, the events are rare, only seen about once a century in any given galaxy. They are only visible to the eye or to ordinary telescopes a few weeks after the initial burst, when the supernova begins to shine brightly-sometimes becoming one of the brightest objects in the evening sky.

Supernovae are remarkable events not only for such displays of power but because they culminate a natural process of stellar renewal-sort of like cosmological compost. As famed physicist Hans Bethe said in 1967, upon winning his Nobel Prize, “Stars have a life cycle much like animals. They get born, they grow, they go through a definite internal development, and finally they die, to give back the material of which they are made so that new stars may live.”

What causes a supernova is that the star's core collapses into a tiny, incredibly dense orb. But the rest of the material in the star collapses as well, and when material from the outer layers of the star falls upon this dense core, it bounces off. This forms a shock wave that races out to the star's edge, and breaks out, creating the enormous burst of X rays like the one that Soderberg and her colleagues captured on tape.

The explosion also creates heavy elements and spreads these elements throughout space. The heavy elements in the universe, including those on Earth, originated long ago in supernova explosions. Some of this matter is radioactive, and its decay over time creates the brightly visible display we associate with supernovae. The accidental discovery of the new supernova in January is significant, says Soderberg, because it demonstrates that the first light of exploding stars are these x-ray bursts. They are like early warning beacons heralding the sometimes luminous display that follows.

Bigger and better telescopes proposed for the future will be able to scan the skies and detect these x-ray bursts routinely from all the nearby galaxies. Grindlay, the Harvard astronomer, is the principle investigator on a candidate future NASA mission called EXIST that will scan the entire heavens every few hours and look for nearby black holes and distant gamma ray bursts. If built, the telescope should be able to detect many supernovae in their first explosive moments-perhaps hundreds a year.
http://www.aip.org/pnu/2008/split/865-1.html

[rduke]

Perhaps if they keep watching that area of that Galaxy... they will see it "blow up" a few more times...

[rangerover777]

I went back to the Supernova pictures and try to understand if this star did have
planets around it or not. It is quite challenging question.
Since the radiation of the exploding star does not go in straight lines as expected
from a blowing mass, instead it creates all kind of shapes, that maybe caused by
colliding with surrounded plants, or their gravity fileds ?

I wonder if anyone can give his mind on that.

Cheers

[nick c]

rangerover777,
In conventional theory a supernova should form a spherical shell around the exploded star, this is not observed. However, the EU describes a supernova as exploding double layers, the result of an overload of galactic currents coming into the star. Instead of a spherical shell of expanding gases we see a plasma organizing into filaments. The electrical currents, which caused the supernova, coming into the system along the axis of the star give it the common hour glass (bipolar) shape. So, that being said, there wouldn't likely be straight lines of a mechanical explosion irregardless of the presence of any planets in the system.
Check these out:
http://www.thunderbolts.info/tpod/2005/ ... c-nova.htm
http://www.thunderbolts.info/tpod/2006/ ... kepler.htm
http://www.thunderbolts.info/tpod/2005/ ... hostar.htm

Nick