Odd Planet Confuses Scientists

eldavojohn writes "While there's been a lot of debate about what is a planet, there is a recent discovery that has scientists even more confused. COROT (COnvection ROtation and planetary Transits) spotted an object that appears to be the size of Jupiter yet is 21.6 times more massive ... and orbits its star in a mere four days and six hours. Now, the other piece of the puzzle is that the star it orbits is more massive and only slightly larger than our Sun. But they can't describe this thing orbiting it. So far they think it is more likely to be a 'failed star' but have settled with 'member of a new-found family of very massive planets that encircle stars more massive than the sun' to describe it accurately."

Good point

[MarkusQ]

Good point. This planet should be about

(0K+6000K)/2
------------------
150000000K

or about 1/50000 the temperature and thus could on that basis be up to 50000 times as dense.

But that can't be the whole picture. At those pressures you'd no longer be dealing with a gas--the volume-per-atom of He would be way out of line. A helium atom occupies about (3.1e-9 cm)^3 or 3e-26 cm^3, and has a mass around 4 * 1.66e-27 kg = 6.66e-24 g, for a per-atom density of about 222 g/cm^3.

So if you could get a core making up maybe 10% of the volume as crystalline helium, I suppose you could do it.

--MarkusQ

Re:Good point

[khallow]

At that temperature and pressure, you no longer are speaking of the normal states of matter that we are familiar with.

Re:What's it made of?

[Fluffeh]

No, gravitational lensing would not change the observations. Gravitation lensing works by bending light through the sheer force of gravity of supermassive objects. Be this slight bend, the light waves are expanded (thereby making them appear closer). If would not however change the size of the star visible, the heat signature it gives off, the wobble caused by the planet or how quickly the planet orbits the sun.

Apart from no-one understanding what formed this planet and why it is so dense, I don't see how this is a big breakthrough. They have found many bigger planets, many faster orbiting planets, many much other things.

I am content just to know that there is a rather heavy planet in orbit somewhere.

Re:Bad Data

[Pantero Blanco]

This was followed up on the astro mailing lists as faulty data -- the observers mistook sunspot-dimming for a planet passing in front of the star. The correction hasn't made it to journalists yet and the science article is still in draft, so no link-to-reference, sorry!

The same thing happened 3-4 weeks back with TW Hydrae b [universetoday.com].

NASA and the ESA's sites still claim this one is valid.

Maybe you could post an excerpt from one of the emails?