A team of astronomers from Penn State and Nicolaus Copernicus University in Poland has discovered a new planet that is closely orbiting a red-giant star, HD 102272, which is much older than our own Sun. The planet has a mass that is nearly six times that of Jupiter, the largest planet in our solar system. The team includes Alexander Wolszczan, the discoverer of the first planets ever found outside our solar system, who is an Evan Pugh Professor of Astronomy and Astrophysics and the director of the Center for Exoplanets and Habitable Worlds at Penn State; and Andrzej Niedzielski, who leads his collaborators in Poland. The team suspects that a second planet may be orbiting HD 102272, as well. The findings, which will be published in a future issue of The Astrophysical Journal, shed light on the ways in which aging stars can influence nearby planets.
Scientists already know that stars expand as they age and that they eventually may gobble up adjacent planets. In fact, scientists expect our own planet to be swallowed up by the Sun in about a billion years. But what scientists don't yet understand fully is how aging stars influence nearby planets before they are destroyed. The team's newly discovered planet is interesting because it is located closer to a red-giant star than any other known planet.
"When red-giant stars expand, they tend to eat up the nearby planets, " said Wolszczan. "Although the planet we discovered conceivably could be closer to the star without being harmed by it, there appears to be a zone of avoidance around such stars of about 0.6 astronomical units, which is a little more than half of the distance from the Earth to the Sun. It is important to find out why planets don't want to get any closer to stars, so one of our next steps is to try to figure out why this zone of avoidance exists and whether it occurs around all red-giant stars."
Not much time to comment here.
Not to be pedantic but the timeframe for worrying about the Earth being engulfed by an evolving Sun is several billion years, not a billion. It's also debatable if the sun will actually expand enough to envelop the Earth, certainly a moot point for any residents given that the oceans and later the atmosphere will have boiled off gigayears beforehand.
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Like I said, no time to comment. I do believe that you are right though.
ReplyDeleteThanx for the compliment on the blog. Now if only my writings would help fund my team.
Very informative , I added it it on my night sky news page. Most of the new planets found are Jupiter like clones. surprised at all of them being the same .
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