Super-Earth / Hot Jupiter Connection ?

Another interesting work presented at the 215th AAS Meeting.

http://www.nasa.gov/centers/goddard/news/topstory/2010/earthlike-exoplanet.html

If this scenario is indeed possible, I wonder if it could explain also the existence of odd balls like HD149026b...

However the hot super-Earths are found in places where the hot Jupiters aren't, so this is probably not the origin for all such planets.

As for HD 149026b, the real problem is assembling enough heavy elements to make that planet's core in the first place... same with some of the very massive cores predicted in other transiting planets.

Hi Lazarus,

Lazarus wrote:

However the hot super-Earths are found in places where the hot Jupiters aren't...

What do you mean by this ?

I think he's talking about the deficit of hot Jupiters in multiple-planet systems. The multiple-planet systems we see that have a close in planet usually has that planet being a super-Earth/Neptune.

I don't think the authors claim that all hot Super-Earths are exposed cores of hot jupiters. Certainly some end up in that position through migration mechanisms.

Also, if the connection between hot Super-Earths and hot jupiters was so linear, I guess one would expect a statistically important number of intermediate, say Saturn-mass, planets close to the host stars, which we don't. This off course assumes that the mass loss is very gradual and not governed by some runaway process which would make observing these intermediate mass bodies difficult.

Yes multiple planet systems are an issue, as is the existence of hot super-Earths around low-metallicity and low-mass stars.

Then again it would be surprising if there weren't any "chthonian planets" out there.

Isn't there supposed to a lot of ice and volatiles in Jupiter/Saturn core.

If so there must have been a period during evaporation when such planets would be almost identical to the water worlds that are being discovered today.

They also seem to imply that the planet moves in closer as it evaporates. I'm curious as to the mechanism that would help it loose so much angular momentum.

As I understand it, the Neptunes are cores that were formed late enough to not be able to accrete a huge H/He envelope, and never became gas giants. So the small objects we are detecting were likely never gas giants to begin with, but rather simply did not accrete a huge H/He envelope, either because they formed later on in their planetary system's history, or there wasn't much in the disk in the first place. This may explain why red dwarfs seem to prefer having ice giants instead of gas giants.

Edit: Moving to mechanics.