Movie time!
Posted on 09/17/2003 7:27:05 AM PDT by bedolido
A giant star has been caught in the act of swallowing three planets, one after the other, with each "meal" accompanied by a massive eruption.
"It has been suggested in the past that stars might engulf planets in this way, but we believe we have actually caught this action for the first time," says Alon Retter of the University of Sydney, Australia.
The star, known as V838 Monocerotis, is about 20,000 light years from Earth. In January 2002, it temporarily became the brightest star in the Milky Way, 600,000 times more luminous than the Sun. At the time, astronomers struggled to explain the spectacular explosion.
Retter and colleague Ariel Marom believe their new analysis of light emissions from the star indicates that it was a red giant that expanded and successively swallowed three relatively massive planets in quick succession. The time between the first and the last engulfment was only about two months.
"In principle, that explanation seems OK," says John Lattanzio, director of the Centre for Stellar and Planetary Astrophysics at Monash University. But he says the star was too hot to have been a red giant. "It was probably one that was on its way there - that could fit the parameters."
Existing models of what will happen when our Sun expands to become a red giant, in about one billion years, suggest that Venus and Mercury will both be engulfed. The likely fate of the Earth is unclear. "Our work suggests that once one planet is engulfed, there is an eruption, and then further expansion - so it might suggest that Earth will indeed be swallowed. But this will need to be checked carefully with the models," Retter says.
Twin peaks
The light analysed from V838 Monocerotis shows that after a short but gradual decline in luminosity following January's outburst, the star suddenly increased in brightness again in early February. The phenomenon was repeated a third time in March.
Retter and Marom found that each of the three maximum peaks in brightness were followed by secondary, weaker peaks. This repeating pattern suggests each event had the same cause, says Retter. The data also reveals the presence of large amounts of lithium and barium, which astronomers had proposed might indicate that a star had swallowed a planet.
Initially it was suggested that the first explosion was some kind of nova outburst, but this was hard to match to the observations. Other researchers suggested that two stars had collided.
"But again, this cannot explain the complicated light curve," Retter says "Our explanation, that the star swallowed three planets, fits all the observational features of the star."
Retter and Marom describe their analysis in a letter accepted by the Monthly Notices of the Royal Astronomical Society.
Emma Young, Sydney
(well SOMEONE had to bring it up ;-)
Just damn.
If you want on the new list, FReepmail me. This IS a high-volume PING list...
Tnx for pointing that out. The image was split arbitrarily right along the galactic plane. I was kind of wondering where the other half of the Milky Way was, and there it is wrapped around the edge of the image.
I thought Monocerotis V838 was the virus that went around last winter?
So9
Indicates a relatively calm star undergoing a bowel examination.
It is obvious that his administration must be fired for allowing this to happen over 40,000 years ago!
Surprised nobody posted this yet.
It is obvious that his administration must be fired for allowing this to happen over 40,000 years ago!
I hope that your wife is not a freeper. Oh, four children. She's too busy to freep!
I'll go out on a limb and say that when our Sun runs out of hydrogen, enters the red giant stage, and engulfs Mercury and Venus, we're f/ked.
Democrats are probably outraged that the Bush administration hasn't created a program to deal with this. After all, we're only talking about a thousand millenia before the unthinkable happens.
I'm no scientist, but if Venus and Mercury are both engulfed, we'll have some real global warming to deal with!
Scientists can't figure out where new ones come from.
This article provides the answer.
HEre is the other thread :comets
Movie time!
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