Giant star caught swallowing three planets

New Scientist ^ | 09/17/03 | Emma Young

[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

[bedolido]

[Pyro7480]

Ping for APOD members.

[Quilla]

[dfwgator]

I thought this article was going to be about Rosie O'Donnell.

[The G Man]

Damn. I thought it was going to turn out to be Michael Strahan. I bet he could probably spit 'em back out with his mouth closed too.

[Consort]

My neighbor has Monocerotis.

[randog]

LOL!

[TheBigB]

...followed by a mutha of a TUMS...

[misterrob]

NASA in conjunction with the Federal Government issued a warning on galactic obesity and suggested that stars refrain from gorging themselves.

[dfwgator]

Strahan probably felt like eating their kicker after Monday Night.

[dfwgator]

Are the planets low in carbs?

[Damocles]

 

I thought it was about Star Jones...

[Mr. Bird]

Famous maybe, but I wouldn't call Michael Moore a "star".

[Tacis]

See, if a democrat had been president, I'm sure that this news would have been so disturbing that we would have passed a law aimed at preventing it and assuring that, for the sake of the children of future generations, it didn't happen again. Heck, there might even have been little frogs, fishies or bugs on any one of those poor planets; darn, there might even have been minority folks on those poor planets.

[4mycountry]

[bedolido]

these pictures remind me of the birth of my four children... without the annoying screaming from my wife

[Joe Bonforte]

Giant star caught swallowing three planets

I didn't know Barry Bonds could eat that much.

[areafiftyone]

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.

That massive eruption is called a SOLAR BURP!!

[StriperSniper]

The star, known as V838 Monocerotis,

affectionately dubbed 'Monica' by the previous administrations science advisor...

[Jonah Hex]

Giant star caught swallowing three planets

Gee, and I thought this was about Mary Carey and the California governor's race.