September 15, 200619 yr http://news.yahoo.com/s/ap/20060914/ap_on_sc/puffy_planet Wow. You'd think scientists could find a better word than "fluffy." Edited September 15, 200619 yr by SoxFan1
September 15, 200619 yr While Earth takes a year to orbit the sun, the newly found planet whips around its star once every 4.5 days That's crazy cool stuff.
September 15, 200619 yr Fluffy planet? That's pretty cool. I love it how they're finding so many more planets but still can kick Pluto out.
September 15, 200619 yr 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. So... terrestrial, jovian, and now fluffy?
September 16, 200619 yr QUOTE(TheBlackSox8 @ Sep 15, 2006 -> 05:41 PM) how can they tell this from 450 light years away? 2 datapoints would give you the density; you need the mass of the planet and the size of the planet. The size of the planet is determined by having the planet move between the star it orbits and the Earth. This causes a temporary drop in the light flux from that planet to a telescope, which can be measured and calculated to give you the size. The mass of the planet you can determine by measuring the motion of the star. If there is a planet of sufficient mass orbiting a star, then the star itself will have some motion relative to the center of mass of the 2 objects. As the sun moves around, it will move towards and away from the Earth in a repetitive cycle. The motion of an object relative to the earth is enough to change slightly the spectrum of light coming from the star, an effect known as the Doppler shift. Therefore, if you measure the frequency and amplitude of the systematic variations in the Doppler shift of light coming from a star, you can calculate the mass of the planet causing the sun's motion and its distance from the sun. So if you get a transit and measure the doppler shift, you have both the mass and the volume of the planet, and you can convert to density.
September 16, 200619 yr QUOTE(TheBlackSox8 @ Sep 15, 2006 -> 08:41 PM) how can they tell this from 450 light years away? See Balta's explaination above, BlackSox. I mean, sheesh, what are you, stoopid or something?
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