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Fraser
2006-Sep-16, 03:10 AM
A new, lightweight planet has been discovered orbiting a star 450 light-years away in the constellation Lacerta. This unusual planet is larger than Jupiter, but it has only half its mass; astronomers estimate it has the same density as cork. The planet, named HAT-P-1, orbits its host star every 4.5 days. A network of automated telescopes detected how the planet dims its parent star by 1.5% when it passes in between the star and the Earth. Why this planet is so swollen is still a mystery to astronomers.

Read the full blog entry (http://www.universetoday.com/2006/09/15/huge-lightweight-planet-discovered/)

Joca
2006-Sep-17, 03:31 PM
There is a misunderstanding in almost all of the news about newly discovered HAT-P-1b. It says it's a "huge" planet, soemwhere even "gigantic", and it all seems to come from one misunderstood sentence:

"With a radius about 1.38 times Jupiterís, HAT-P-1 is the largest known planet."

This statement is true, but from "largest known planet" doesn't necessarily follow the epithet "huge". Radius of an exoplanet can be determined only if its transit has been observed. Since there are only about a dozen of such planets, with the largest planet until now being OGLE-TR-10 having a radius of ~1.3 that of Jupiter, HAT-P-1b really is "the largest known planet", but can by no means called "huge".

Cheers,
Jovan, http://www.xsmagazine.co.nr/

pantzov
2006-Sep-18, 08:16 AM
heh heh , i love it every time there are holes poked in these theories that everyone seems so certain of these days.

i guess that if the circumstances that tip a planet on its side are so "unusual" then we should consider ourselves very lucky to have such a close example. or maybe there's one more idea that needs to be reexamined???

Sagarika
2006-Sep-18, 10:33 AM
A new, lightweight planet has been discovered orbiting a star 450 light-years away in the constellation Lacerta. This unusual planet is larger than Jupiter, but it has only half its mass; astronomers estimate it has the same density as cork. The planet, named HAT-P-1, orbits its host star every 4.5 days. A network of automated telescopes detected how the planet dims its parent star by 1.5% when it passes in between the star and the Earth. Why this planet is so swollen is still a mystery to astronomers.

Read the full blog entry (http://www.universetoday.com/2006/09/15/huge-lightweight-planet-discovered/)

Finally, my information about such stars or planets is emerging as the truth. I've recently quoted that we have such planets within Milky Way and those are revolving around the sun alike planet (but doesnt look like the sun). HAT-P-1 is out of the Milky Way, but we have such stars and planets within the Milky Way...so, Good Luck...

John Mendenhall
2006-Sep-18, 04:51 PM
If it's the largest known planet, then I think it's huge by definition.

Joca
2006-Sep-21, 09:13 PM
I don't think so.. Especially because it's only a little larger than HD 209458b [1.36 vs. 1.32 Rj], and no one ever thought of calling HD 209458b huge. I just think it gives the wrong idea to the people reading those articles.

Cheers,
Jovan, http://www.xsmagazine.co.nr/

RUF
2006-Sep-30, 05:10 AM
i guess that if the circumstances that tip a planet on its side are so "unusual" then we should consider ourselves very lucky to have such a close example. or maybe there's one more idea that needs to be reexamined???
In fact, it was the Sun and the other eight, (er..seven) planets that were all tipped on thier side -- Uranus is the only one that wasn't.:D

Tuckerfan
2006-Oct-01, 06:53 AM
Something occured to me tonight while listening to the Universe Today podcast discussing this. From what we can tell, it's large and apparently has some kind of heat source in the center so that it's warmer than Jupiter. How do we know that it's not artificial? Could it be something like a Dyson sphere, with an artificial sun in the middle? I know what you're thinking, "Well, if they've got the technology to do that, why'd they make such a small body and not make one large enough to fill the entire orbit?" Well, I've heard conflicting stories on the possibility of Dyson spheres. One is that there's no enough mass in our solar system to build one (which could a possibility in theirs) another is that there'd be problems with keeping it properly positioned around a star. Even if that's not the case in this system, there might be other factors at play which could cause them to want to live in such a set up. One is that there may be something about their star which prohibits the building of a Dyson sphere. The next is that there might be life on other worlds in that system and they don't want to disrupt them to create a sphere. Finally, perhaps it's an intermediate stage in building a Dyson sphere (after all, they have to live somewhere while the thing's being built, right?).