New Kepler Planet....10b

[renormalised]

The team of the Kepler mission have just announced the discovery of a new exoplanet, Kepler 10b. It's about 1.4 times the size of the Earth, 4.6 times as massive and has an average density of 8.8g/cm^3....basically it's a giant iron wrecking ball with a thin veneer of silicates. A super Mercury, if you will. Here's the link to the physical parameters of the system...

http://kepler.nasa.gov/Mission/discoveries/kepler10b/

and the discovery page....

http://kepler.nasa.gov/news/nasakeplernews/index.cfm?FuseAction=ShowNews&NewsID=94

[mswhin63]

Thanks for the info, always interested in new finding on the planetary scale :)

I have been using plantethunter.org site to see if I can find something as well.

[renormalised]

Yeah, Malcolm, that is an interesting site. I joined up there about a month ago, now. Been doing some looking at the light curves and helping out the less knowledgeable members. Some very interesting results have turned up. Quite a few eclipsing binaries amongst the data.

[mswhin63]

Yeah it is interesting, I was also wondering if some of the irregular luminance are star wobbling with the star going out of the field of view of the detector, but without knowing the technical aspect of the imaging I wouldn't know.

[CraigS]

Hmm … interesting …



Its interesting that this is the first rocky planet with 'solid evidence'.

The second paragraph compares it with Mercury. Its interesting that in spite of Mercury's closeness to the Sun, there's still frozen water there. Is Mercury in the 'habitable zone' ?

One wonders how close an exoplanet could get to a star, and still have some kind of water present … (?)… is the habitable zone defined primarily, by the presence/absence of liquid water ?

:question:

Cheers

[mswhin63]

Just received an update on iPhone Exoplanet and Kepler 10b is way out of the habitable zone even closer to the star in relation to Mercury in our solar system.

I wouldn't be surprise there are more planets in that system, it only need to be watched for more time possible 1 or 2 years to register more dips hopefully.

I can't image life as we would have it be pleasant if the rotation around the sun was only a few days.

[renormalised]

Mercury in the habitable zone.....no. It's too close to the Sun and the water there only exists in those craters deep enough to have a permanent shadow existing within their walls....i.e. at the poles of the planet. Mind you, the ice only exists because of this and the fact its covered in regolith, which protects it from flash vapourising into the vacuum of space. Doesn't need much dirt on top, but it's needed to act like a "bottle" for the ice.

A HZ is defined in several ways, but one is the zone where the temperatures on the surface of a world are conducive to the presence of water in its liquid form.

Let's just say that Kepler 10b is quite dry, even on its dark side. Apart from the heat, the high energy radiation there would disrupt water molecules from forming. If it did exist, it would have to be covered in quite a lot of regolith (to protect it from the radiation and also the heat). However, depending on where that planet formed (not where it is, but at least out as far as the Earth), the early conditions in the inner accretion disk around the star would've precluded the formation of water anyway....too hot.

[renormalised]

The planet is spin-orbit coupled most likely, which means its rotation rate is synchronised with its orbit....roughly 20.2 hours. So one side always faces its parent star and the other side is in permanent darkness.

[CraigS]

So where did Mercury's water come from ?

Cheers

[renormalised]

From the Sun......hydrogen ions in the solar wind interacting with oxygen atoms in the surface soil minerals within the craters. Basically, oxydised solar wind :)