相关论文: Evolution of "51Peg b-like" Planets
Stellar irradiation and particles forcing strongly affect the immediate environment of extrasolar giant planets orbiting near their parent stars. Here, we use far-ultraviolet emission spectra from HD209458 in the wavelength range…
So far, the atmospheres of non-transiting exoplanets remain poorly explored, and the potential of high-resolution spectroscopy for determining key planetary parameters beyond their atmospheric properties has not been fully exploited. We…
An intriguing, growing class of planets are the "super-puffs," objects with exceptionally large radii for their masses and thus correspondingly low densities ($\lesssim0.3\rm\,g\,cm^{-3}$). Here we consider whether they could have large…
Recent observations of the Earth's exosphere revealed the presence of an extended hydrogenic component that could reach distances beyond 40 planetary radii. Detection of similar extended exospheres around Earth-like exoplanets could reveal…
Context: Recently, the He I triplet at 10830 \r{A} has been rediscovered as an excellent probe of the extended and possibly evaporating atmospheres of close-in transiting planets. This has already resulted in detections of this triplet in…
HD17156b is a newly-found transiting extrasolar giant planet (EGP) that orbits its G-type host star in a highly eccentric orbit (e~0.67) with an orbital semi-major axis of 0.16 AU. Its period, 21.2 Earth days, is the longest among the known…
Extra-solar planets close to their host stars have likely undergone significant tidal evolution since the time of their formation. Tides probably dominated their orbital evolution once the dust and gas had cleared away, and as the orbits…
We have observed 4 transits of the planet of HD 209458 using the STIS spectrograph on HST. Summing the recorded counts over wavelength between 582 nm and 638 nm yields a photometric time series with 80 s time sampling and relative precision…
The rich wealth of observational data, and matching theoretical investigations, of the transiting planet of HD209458 stands in sharp contrast to systems for which only the radial velocity orbit is known. In this paper, I summarize the…
We calculate the theoretical evolution of the radii of all fourteen of the known transiting extrasolar giant planets (EGPs) for a variety of assumptions concerning atmospheric opacity, dense inner core masses, and possible internal power…
Planet formation occurs around a wide range of stellar masses and stellar system architectures. An improved understanding of the formation process can be achieved by studying it across the full parameter space, particularly toward the…
The first mass-estimate of an exoplanet around a Sun-like star, 51 Peg b and the first radius measurement of an exoplanet, HD209458b pointed to the challenges of understanding the atmosphere, interior, and evolution of exoplanets including…
We present B, V, R, I and Z-band photometric observations of HD 209458 during the transit by its planetary companion on UT 1999 November 15 with the University of Hawaii 0.6m and 2.2m telescopes and the High Altitude Observatory STARE…
Around low- and intermediate-mass (1.5-3 M_sun) red giants, no planets have been found inside 0.6 AU. Such a paucity is not seen in the case of 1 M_sun main sequence stars. In this study, we examine the possibility that short-period planets…
We investigate the migration of massive extrasolar planets due to gravitational interaction with a viscous protoplanetary disc. We show that a model in which planets form at 5 AU at a constant rate, before migrating, leads to a predicted…
Giant planets on long period orbits around the nearest stars are among the easiest to directly image. Unfortunately these planets are difficult to fully constrain by indirect methods, e.g., transit and radial velocity (RV). In this study,…
To aid in the physical interpretation of planetary radii constrained through observations of transiting planets, or eventually direct detections, we compute model radii of pure hydrogen-helium, water, rock, and iron planets, along with…
Atomic hydrogen escaping from the extrasolar giant planet HD209458b provides the largest observational signature ever detected for an extrasolar planet atmosphere. In fact, the upper atmosphere of this planet is evaporating. Observational…
We report the detection of a Jupiter-mass planet in a 6.838 day orbit around the 1.28 solar mass subgiant HD 185269. The eccentricity of HD 185269b (e = 0.30) is unusually large compared to other planets within 0.1 AU of their stars.…
Absorption of high-energy radiation in planetary thermospheres is believed to lead to the formation of planetary winds. The resulting mass-loss rates can affect the evolution, particularly of small gas planets. We present 1D, spherically…