Posted on 09/14/2006 9:59:07 AM PDT by NormsRevenge
WASHINGTON - The largest planet ever found orbiting another star is so puffy it would float on water, astronomers said Thursday.
The newly discovered planet, dubbed HAT-P-1, is both the largest and least dense of the nearly 200 worlds astronomers have found outside our own solar system. HAT-P-1 orbits one of a pair of stars in the constellation Lacerta, about 450 light-years from Earth.
"This new planet, if you could imagine putting it in a cosmic water glass, it would float," said Robert Noyes, a research astrophysicist with the Smithsonian Astrophysical Observatory.
HAT-P-1 is an oddball planet, since it orbits its parent star at just one-twentieth of the distance that separates Earth from our own sun. While Earth takes a year to orbit the sun, the newly found planet whips around its star once every 4.5 days.
Astronomers believe HAT-P-1 may belong to an entirely new class of planets, along with a second, smaller distant world that's also puffier than theories would have predicted, Noyes said.
Astronomers used a network of telescopes in Arizona and Hawaii to discover the planet. Its parent star is too faint to see with the naked eye but can be spied with binoculars.
This artist rendering provided by the Harvard-Smithsonian Center for Astrophysics shows the newly discovered world HAT-P-1. The newly discovered planet is both the largest and least dense of the nearly 200 worlds astronomers have found outside our own solar system. HAT-P-1 orbits one of a pair of stars in the constellation Lacerta, about 450 light-years from Earth. (AP Photo/Harvard-Smithsonian Center for Astrophysics, David A. Aguilar)
On the Net:
Harvard-Smithsonian Center for Astrophysics: http://www.cfa.harvard.edu/
Press Release
http://www.cfa.harvard.edu/press/pr0624.html
The newly discovered world HAT-P-1 has baffled astronomers, since it is puffed up much larger than theory predicts. HAT-P-1 has a radius about 1.38 times Jupiter's but contains only half Jupiter's mass.
I suspect all these giant planets whipping around their primaries in two-day orbits are going to turn out to be artifacts of piss-poor computer models.
These large gaseous planets have really knocked the old solar system formation theories for a loop. The way I learned the stuff in the 70s and 80s, large gaseous planets couldn't exist so close to their suns.
Just goes to show that science should never be taken as a matter of faith.
You've gotta love the headline :)
:') It's super-absorbent! Away with floods! Away with workaday tidal waves!
Thanks for the topic and graphics. "a radius about 1.38 times Jupiter's but contains only half Jupiter's mass" means that somethin's up with HAT-P-1 and/or its discoverers. ;')
A planet this close to a star shouldn't have any ices or gases left; a planet this massive should be a molten ball of iron and silicates with a density greater than 5 g/cc. I would hate to jump to any conclusions...
planetary science ping
;')
Strange New Planet Baffles AstronomersGaspar Bakos, a Hubble fellow at CfA... designed and built the HAT network and is lead author of a paper submitted to the Astrophysical Journal describing the discovery... "This planet is about one-quarter the density of water," Bakos said. "In other words, it's lighter than a giant ball of cork! Just like Saturn, it would float in a bathtub if you could find a tub big enough to hold it, but it would float almost three times higher."
by Staff Writers
Sep 15, 2006
HAT-P-1's parent star is one member of a double-star system called ADS 16402 and is visible in binoculars. The two stars are separated by about 1500 times the Earth-Sun distance. The stars are similar to the Sun but slightly younger - about 3.6 billion years old compared to the Sun's age of 4.5 billion years.
Although stranger than any other extrasolar planet found so far, HAT-P-1 is not alone in its low-density status. The first planet ever found to transit its star, HD 209458b, also is puffed up about 20 percent larger than predicted by theory. HAT-P-1 is 24 percent larger than expected.
"Out of eleven known transiting planets, now not one but two are substantially bigger and lower in density than theory predicts," said co-author Robert Noyes (CfA). "We can't dismiss HD209458b as a fluke. This new discovery suggests something could be missing in our theories of how planets form."
This new planet is even fluffier than Saturn. Three times fluffier. Doesn't seem possible.
So THAT's what happened to the Stay-Puft Marshmallow Man at the end of Ghostbusters!
heh heh
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
