Celestia Forums

I don't understand english very well, but it seems to me that the ESO (European Southern Observatory) as observed curious properties of 2 new exoplanets: See http://www.eso.org/outreach/press-rel/pr-2004/pr-11-04.html#phot-14a-04
Jeam

I've already added these two new OGLE transiters to extrasolar.ssc - get the current version on the CVS tree at http://cvs.sourceforge.net/viewcvs.py/celestia/celestia/data/extrasolar.ssc. Both stars are absent from stars.dat so to see the new planets you'll also need to get my revised exoplanet stars add-on from Selden's site, at http://www.lns.cornell.edu/~seb/celestia/hutchison/missing-stars.html. (If you have a previous version of this stars add-on, remember to delete it from your extras folder - the linked webpage tells you how to recognize a previous version if there's one there.)

Grant

granthutchison wrote:I've already added these two new OGLE transiters to extrasolar.ssc - get the current version on the CVS tree at http://cvs.sourceforge.net/viewcvs.py/celestia/celestia/data/extrasolar.ssc. Both stars are absent from stars.dat so to see the new planets you'll also need to get my revised exoplanet stars add-on from Selden's site, at [url]Grant

Effectivily, I've do not take a look at your revised add-on for a while. Thanks Grant. Jeam

Jeam Tag wrote:Effectivily, I've do not take a look at your revised add-on for a while.

Sorry, Jeam - I was not trying to criticize you. Just letting other people know that they could look at these objects in Celestia if they wanted to.

Grant

granthutchison wrote:Sorry, Jeam - I was not trying to criticize you. Just letting other people know that they could look at these objects in Celestia if they wanted to.Grant

No problem, I don't take this as a criticism: as I said, this was a good idea to remember all Celestians that there are constantly many little improvments that aren't systematically announced on the forum: just that we don't always think to search them!. I Think I must render this more explicit in my pages, too. Jeam

How they know that now are gas giants?Were the others terrestrial giants?Anyway,it was discovered planets with almost the same massof Jupiter near the star,like 51 Pegasi.I don?t understand why should be a new class of planet.Why?

The hot jupiter around OGLE-TR-113 is, according to that link, 35% heavier and has a 10% larger diameter than Jupiter; these are gas giant densities. It seems likely that the high temperature of such a world would mean the atmosphere is gradually boiling off, making a comet-like tail; but it will take many hundreds of millions or even a few billion years for a jupiter sized planet to evaporate down to the solid core, if any.

There aren't any big solid terrestrial worlds in the Jupiter mass range because they would always have a big deep atmosphere, even if they were a couple of million kilometers from the star.

A bit more about 'very hot jupiters' here
http://vega.lpl.arizona.edu/~gilda/extrass.html

danielj wrote:How they know that now are gas giants?Were the others terrestrial giants?Anyway,it was discovered planets with almost the same massof Jupiter near the star,like 51 Pegasi.I don?t understand why should be a new class of planet.Why?

The newly-discovered planets orbit much closer than typical 51 Pegasi-type planets. No planet orbiting under 2 days have been found with the radial velocity method, but all the OGLE planets orbit under 2 days.

There may be some physical reason why a hot Jupiter doesn't usually become a super-hot Jupiter (like the inner edge of the protoplanetary disc; all close-orbiting giant planets are tought to have formed much further out and dragged inward possibly by the protoplanetary disc).

If I remember correctly, about one Sunlike star in a hundred has a hot Jupiter, but only one star in 2-3 thousand has a super-hot Jupiter.

Just a question, is "Osiris" (HD 209458 b) a member of this class?

chaos syndrome wrote:Just a question, is "Osiris" (HD 209458 b) a member of this class?

Evidently not - Jeam's link states that the three OGLE transiters TR-56, TR-113 and TR-132 define the class of "very hot jupiters", by having periods shorter than 2.5 days. Hot jupiters with periods > 3 days, like HD 209458 b, are relatively common.

Grant