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Fraser
2007-Jun-26, 04:29 PM
Supernovae are rare events, only occurring once every 25-100 years in galaxy. So it came as a complete surprise when NASA's Swift satellite turned up two supernovae going off at the same time in a galaxy - separated by only 16 days. ...

Read the full blog entry (http://www.universetoday.com/2007/06/26/double-supernovae-discovered/)

Kullat Nunu
2007-Jun-26, 09:32 PM
This is a complete coincidence. The two events are separated by tens of thousands of light years of space. In fact, an astronomer in the galaxy might see the two events separated by thousands of years.

Not to mention that their distances to Earth may differ by many thousands of years which means an observer located at exactly same distance from both supernovas would see thousands of years passing between the two events. We happen to be located in a lucky spot where the light from both events reached us almost simultaneously (well, in the scale of hundreds of millions of years 16 days is a blink of eye...).

Don Alexander
2007-Jun-27, 11:45 AM
This is really quite cool.

Although it is not the first time something like that has happened. Don't remeber the names... But some years back, two SNe also went off in the same galaxy just a month or so apart. As astronomers were relatively steadily observing the first one, the second one was caught within a day or so of explosion, which is rare.

Don Alexander

Palomar
2007-Jun-27, 11:59 AM
Supernovae are rare events, only occurring once every 25-100 years in galaxy.

That has always surprised me, considering how many stars the "average" galaxy contains. Seems it should be more routine than that.


So it came as a complete surprise when NASA's Swift satellite turned up two supernovae going off at the same time in a galaxy - separated by only 16 days. ...

Cool. What a pity it's a rarity; seems that should be somewhat of a "norm."

Kullat Nunu
2007-Jun-28, 10:14 PM
That has always surprised me, considering how many stars the "average" galaxy contains. Seems it should be more routine than that.

Well, a star has to be over eight times as massive as the Sun in order to blow up (or to be a white dwarf near the Chandrasekhar limit); both objects are very rare, so it is not a surprise. In fact, I think it is incredible that they're that common. It tells something about how huge amount of stars there are in a large galaxy like the Milky Way.


Cool. What a pity it's a rarity; seems that should be somewhat of a "norm."

I don't mind not having exploding stars in my neighborhood...

Nick4
2007-Jul-01, 06:31 AM
Thats crazy a dubble supernova...thats like winning the lotto in astronomy.