Intense Photometry of the Exotic Exoplanet HD 149026b

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Transiting planet HD 149026b is unique. Its mass and radius together indicate a heavy-element core of about 80 Earth masses, more than all the heavy elements in the solar system outside the sun. We made the first direct measurement of this planet in a Director's Discretionary Time (DDT) program, detecting a flux 0.00084 +- 0.00011 times that of its parent star. The corresponding brightness temperature is 2300 +- 200 K, making this the hottest of all measured planets. It is much hotter than the equillibrium temperature for zero albedo and uniform emission (1741 K). Even with instantaneous re-emission of all received stellar radiation, the planet needs zero albedo to achieve this temperature in a blackbody model. More realistic models predict lower planetary emission. Models with hot stratospheres emit enough, but we have not so far found one that is self-consistent. Our goals here are to obtain several secondary-eclipse measurements in all accessible bandpasses, which will provide S/N sufficient to distinguish among models, and to observe one transit at 8 microns. The latter is necessary because the area ratio with the star is unfavorable for ground-based transit radius measurements of sufficient accuracy to constrain models well. This measurement will be more accurate than is possible with any other telescope. The eclipses will test composition models of Fortney, Seager, and others, will test for variability, and will investigate an intriguing 1.7-sigma mismatch between the DDT eclipse timing and the best ground-based prediction. During our DDT analysis, we discovered and corrected several previously-unknown systematic errors, and established the optimum program for observing extrasolar planet transits with Spitzer. These will thus be the highest-accuracy measurements of this exotic planet until JWST.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Intense Photometry of the Exotic Exoplanet HD 149026b does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Intense Photometry of the Exotic Exoplanet HD 149026b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Intense Photometry of the Exotic Exoplanet HD 149026b will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1747337

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.