Young gas giants fly close to their suns

[PF_SpaceNews]

Young gas giants fly close to their suns

Hot Jupiters, giant Jupiter-like exoplanets that orbit 20 times closer to their host stars than the Earth does to the Sun, can form and migrate towards their infant stars in as little as a few million years, researchers at the University of St Andrews have discovered.

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[Greg Bernhardt]

So that would be like as close as Mercury? Is it odd that they are gas planets?

 

[Drakkith]

So that would be like as close as Mercury?

Closer than Mercury. MUCH closer in some cases. TrES-3b, a gas giant around the star GSC 03089-00929, has an orbital radius of just 0.0226 AU, which is about 17 times closer to its star than Mercury is from the sun.

Is it odd that they are gas planets?

Indeed. They shouldn't be able to form that closely to their stars, which is why it is believed that they form further away and end up migrating through orbital interactions.

 

[mfb]

I think you lost a "not" Drakkith.

There are so many different types of planetary systems - some have hot Jupiters, most have not. It leads to the question where the difference comes from. Is the formation of them a rare process? Do most hot Jupiters fall into the star and disappear?
I guess other planets would have a hard time surviving such a migration process, so looking for planets orbiting outside of hot Jupiters sounds interesting.

 

[Drakkith]

I think you lost a "not" Drakkith.

Corrected.