Sentences with word «subgiant»
A "subgiant" is a star that is in a transitional stage between being a regular main sequence star (like our Sun) and an evolved giant star. It is larger and hotter than a main sequence star, but smaller and cooler than a giant star. Full definition
Future monitoring of the transits of this system may enable the detection of period decay and constrain the tidal dissipation rates of subgiant stars.
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Star A is probably a yellow - orange subgiant of spectral and luminosity type G0 IV (NASA Stars and Exoplanet Database; and Garrison and Beattie, 1998).
Our stellar sample ranges from M dwarfs with masses as low as 0.2 Msun to intermediate - mass subgiants with masses as high as 1.9 Msun.
Lambda Serpentis is a main sequence dwarf star of spectral and luminosity type G0 V, but it is listed as a possible subgiant in some catalogues.
HAT - P - 67b: an extremely low density Saturn transiting an F - subgiant confirmed via Doppler tomography.
Star A is probably a yellow - orange subgiant of spectral and luminosity type G0 IV).
The primary component in the system is a spectroscopic binary with the stellar classification of B2 IV, matching the spectrum of a blue - white subgiant star.
Schlaufman, K. C. & Winn, J. N. Evidence for the tidal destruction of hot Jupiters by subgiant stars.
Evolutionary analysis of the host star suggests that KELT - 10b is unlikely to survive beyond the current subgiant phase, due to a concomitant in - spiral of the planet over the next $ \ sim $ 1 Gyr.
According to Professor Jim Kaler at the University of Illinois» Department of Astronomy, Rana started life as a main sequence F8 dwarf (somewhat hotter and brighter than Sol with slightly greater mass) around 7.5 billion years ago, but core hydrogen fusion has ceased causing the star to expand and cool as an active subgiant before becoming much brighter and larger «as a true giant star» through core helium fusion.
Tau Boötis A is a yellowish main sequence dwarf star of spectral and luminosity type F7 V, although it has also been classified as a F6 IV subgiant.
Delta Eridani is a orange - red subgiant (K0 IVe) that has about 2.3 to 2.7 times Sol's diameter and about 2.8 times its luminosity.
Because K2 - 39b has a short orbital period, its existence makes it seem unlikely that tidal destruction is wholly responsible for the differences in planet populations around subgiant and main - sequence stars.
Kepler photometry and Keck - HIRES radial velocities yield the radius and mass of the planet around this F8IV subgiant host star.
6 G. Piscium is a yellow subgiant star with the stellar classification of G8 IV.
The system is composed of a blue - white giant with the stellar classification of B9III - IV and a visual magnitude of 5.33, a white subgiant belonging to the stellar class A0IVMn with an apparent magnitude of 5.63, and a star with a magnitude of 8.5 separated from the second component by 37.7 arc seconds.
Retired A stars and their companions: exoplanets orbiting three intermediate - mass subgiants.
Beta Hydri is also the closest confirmed subgiant star to Sol and one of the older as well as highly evolved stars of the Sun's spectral class in the Solar neighborhood.
It appears to be a subgiant star that is evolving off the main sequence, as it begins to fuse the increasing amounts of helium «ash» mixed with hydrogen at its core.
Altair has the New Suspected Variable designation NSV 24910 and is unusually bright for its spectral type and so may be becoming a subgiant star that is beginning to evolve off the main sequence, as it begins to fuse the increasing amounts of helium «ash» mixed with hydrogen at its core.
Highly evolved with a lot of helium ash at its core, the star is close to becoming a subgiant (Wulff Dietz Heintz, 1988, page 1074, see: BD +49 857).
According to Emeritus Professor Jim Kaler, Beta Hydri entered the main sequence a dwarf star at the cooler end of class F (probably around spectral class F8) but now appears to be a subgiant star that is evolving off the main sequence, as it begins to fuse increasing amounts of helium «ash» mixed with hydrogen at its core.
As a subgiant star subject to pulsations which affect careful measurements of variations in radial velocity caused by the gravitational pull of substellar companions, astronomers would find it very difficult to detect any Earth - type planet around Beta Hydri using present methods.
The great spread in luminosities and colours of giant, supergiant, and subgiant stars is also understood to result from evolutionary events.
Since Beta Hydri has become a subgiant, it is possible that any planet that held Earth - like conditions earlier in the system's past has now become too hot to support Earth - type life, but that a colder Mars - type planet has become more Earth - like.
© Torben Krogh & Mogens Winther, (Amtsgymnasiet and EUC Syd Gallery, student photo used with permission) HD 181433 is an orange - red star (similar to Epsilon Eridani at left center of meteor) that may have already evolved into a subgiant, but is probably not yet a giant, star.
HD 181433 may be a subgiant rather than a main - sequence, orange - red dwarf star (Sousa et al, 2008; and ARICNS), but is probably not an giant, star (SIMBAD) of spectral and luminosity type K3 - 5 V - III.
Achernar is a blue - white main sequence star of spectral and luminosity type B3 Vpe (Hiltner et al, 1969), that previously had been classed as bright as a subgiant.
Since Delta Eridani has become a subgiant, it is possible that any planet that held Earth - like conditions earlier in the system's past has now become too hot to support Earth - type life, but that a colder Mars - type planet has become more Earth - like.
As a subgiant star subject to pulsations which affect careful measurements of radial velocity, astronomers would find it very difficult to detect any Earth - type planet arond this star using present methods.
With an orbital period of 4.6 days, it is the shortest - period planet orbiting a subgiant star known to date.
As a subgiant, the star has entered the post-main-sequence phase of evolution having exhausted core hydrogen and transitioned to the hydrogen - shell - burning phase around a helium - rich core, evolving toward the red giant branch (di Mauro et al, 2003).
Marginal cases are allowed; for example, a star may be either a supergiant or a bright giant, or may be in between the subgiant and main - sequence classifications.
The star is poised to evolve off the main sequence into a subgiant, as it is close to or just past the end of core hydrogen burning (North et al, 2009; and Eggenberger and Carrier, 2006).
For example, a star classified as A3 - 4III / IV would be in between spectral types A3 and A4, while being either a giant star or a subgiant.
Life on an Earth - like planet, however, may have developed closer to the star before it evolved and began heating up out of the main sequence into a subgiant, thereby shifting its habitable zone outwards away from the star.