Planet being blown away...

[Brian G Turner]

Potentially interesting new article on the Scientific American website here.

Basically, it's the suggestive observation of a Jupiter mass planet in close orbit about a star, with its atmosphere in the process of being extensively blown away by the solar wind.

 

[mac1]

The power of solar wind is truly awesome. But obviously for them to have found thi planet its mass must be huge, and its distance from the star very low. It is however a facinating phenomena, its basically a gas giant with a comets tail, being torn apart by solar wind. The power of solar wind is hugely underestimated by the general public, as I have mentioned elsewhere, scientists have now placed the heliopause at roughly 4 times the distance of Pluto. One thing I would love to do at some stage would be to go to Norway and witness the Aurora Borealis firsthand. They look beautiful on the television, a true testament to the power of our sun.

 

[Survivor]

What I wonder is how this planet got there in the first place. Did it aggregate further out and then infall as the result of impacts or what?

 

[Brian G Turner]

Apparently, Jupiter-mass planets are very commonly in a very close orbit of a parent star, though it seems to be a general process of momentum loss over time.

The interesting thing about the example in the original post is the idea that, not only can it's atmosphere be detected (originally reported here in 1999), but also that the dynamic state of the atmosphere can apparently be inferred.

www.exoplanets.org is a great resource on the subject, but this table of all apparently detected planets, their masseses, orbital period, and eccentricity, may prove of particular interest.

 

[Survivor]

They key word here is "apparently". The fact is that Jupiter class or larger planets close to their primary are pretty much the only kind of planet we can detect so far. If there were a stellar system just like ours out there, then we would have no chance of detecting its planets at our current level of technology.

 

[Brian G Turner]

Certainly, the methodoly has terribly limitations. I strongly suspect that a lot of the time they are simply unable to perceive multiple systems where one or more large mass planets is in close proximity to the star in question. I also wonder at how many of these more distant "jupiters" actually represent a greater degree of planetary complexity, imperceptable with current methods of detection.

There are claims of mulitple systems out there though - details posted here on exoplanets.org.

Btw - think I assumed this was the first measurement of an atmosphere, but that event was actually reported some times ago here.

And if memory recalled a small news item about a detected planet which apparently had iron raining through it's atmosphere. Couldn't access it at "New Scientist", and when searched found reference to a CNN article apparently removed - but I did run a check through Google and found these two following reports, which pursue quite different angles: SeattlePi and Spacedotcom.


just rana and found these reports:

 

[nemesis]

The whole method involved means no clear conclusions. It could be two planets. It is likely that many of the planets discovered become perceived as multiple systems at a later date. This is simply speculation nothing else but well grounded. Still limited.