HD 80606 b (also Struve 1341 B b or HIP 45982 b) is a superjovian planet (Eccentric Jupiter) 190 light-years distant in the constellation of Ursa Major. The planet was discovered orbiting the star Struve 1341 B in April 2001 by a team led by Michel Mayor and Didier Queloz. Based on its mass, at 4 times that of Jupiter, it is a gas giant. This is a simulated mission to the exoplanet HD 80606 b. HD 80606 b is a giant planet with a comet-like orbit; while it spends most of its time at 0.8 A.U. HD 80606b is about 190 light-years away. Its 111-day orbit takes it almost as far away from its star as Earth is from the sun, but at its closest approach, it sweeps blisteringly close to the star for a brief period. The astronomical object called HD 80606b is a Extra-solar Confirmed Planet: Origin of the objects types: (Ref) Object type as listed in the reference 'Ref' (acronym) Object type linked to the acronym according to the original reference.

Planet Migration and Binary Companions: The Case of HD 80606b

Abstract

The exosolar planet HD 80606b has a highly eccentric (e=0.93) and tight (a=0.47 AU) orbit. We study how it might arrive at such an orbit and how it has avoided being tidally circularized until now. The presence of a stellar companion to the host star suggests the possibility that the Kozai mechanism and tidal dissipation combined to draw the planet inward well after it formed: Kozai oscillations produce periods of extreme eccentricity in the planet orbit, and the tidal dissipation that occurs during these periods of small pericenter distances leads to gradual orbital decay. We call this migration mechanism the ``Kozai migration.' It requires that the initial planet orbit be highly inclined relative to the binary orbit. For a companion at 1000 AU and an initial planet orbit at 5 AU, the minimum relative inclination required is ~85°. We discuss the efficiency of tidal dissipation inferred from the observations of exoplanets. Moreover, we investigate possible explanations for the velocity residual (after the motion induced by the planet is removed) observed on the host star: a second planet in the system is excluded over a large extent of semimajor axis space if Kozai migration is to work, and the tide raised on the star by HD 80606b is likely too small in amplitude. Last, we discuss the relevance of Kozai migration for other planetary systems.

• Stars: Planetary Systems;
• Stars: Individual: Henry Draper Number: HD 80606b;
• Astrophysics

Hd 80606 B

Astronomers worldwide staggered into work this morning, some of them rudely elbowing their way to the front of the lines at the espresso machines, clear evidence that events surrounding the January 2010 ‘606 holiday season have finally drawn to a close.

Hopefully the data will turn out to be of high quality! As I mentioned in yesterday’s post, ground observers in both Europe and North America were out in force for the event, collecting photometric and spectroscopic data. The action was covered from space as well. We were awarded a generous 84-hour block of time on Warm Spitzer. The telescope started collecting 4.5-micron photometry more than a day prior to the secondary transit, and ended more than two days after the periastron passage.

What do we hope to learn? By observing the run-up to the secondary transit, we should be able to establish an improved baseline temperature for the planet, which should afford a better sense of how much tidal heating is occurring. And during the days following periastron, we expect to see a near-complete drop-off in flux from the planet as the periastron nightside hemisphere rotates fully into view. The 2007 observations came to a frustrating end just as this should have been starting to occur.

In addition to the secondary eclipse and the ground-based observations, Guillaume Hebrard and his collaborators were awarded 19 hours on Warm Spitzer to observe the primary transit at 4.5 microns. Their photometric time series will enable an improved radius measurement for the planet — both because of the highly accurate photometry and because the effects of stellar limb darkening are negligible in the infrared. Their time series will establish a very precise ephemeris for the transit, which will enable future observations to monitor the system for orbital precession.

Hd 80606 B

Looking forward to the results…