Sentences with phrase «main sequence stars with»

As a highly evolved and relatively cool orange - red giant, single star, Pollux is not much like its «twin» star Castor, which is actually composed of three sets of binary stars (as many as four bluish - white, main sequence stars with two fainter companions).

We aim to determine the level of near - infrared exozodiacal dust emission around a sample of 42 nearby main sequence stars with spectral types ranging from A to K and to investigate its correlation with various stellar parameters and with the presence of cold dust belts.

We aim to determine the level of near - infrared exozodiacal dust emission around a sample of 42 nearby main sequence stars with... ▽ More (Abridged) Dust is expected to be ubiquitous in extrasolar planetary systems owing to the dynamical activity of minor bodies.

Kepler - 10 is a relatively old (11.9 + / - 4.5 Gyr) but otherwise Sun - like Main Sequence star with Teff = 5627 + / - 44 K, Mstar = 0.895 + / - 0.060 Msun, and Rstar = 1.056 + / - 0.021 Rsun.

Theta Volantis is a white main sequence star with the stellar classification A0V.

Not exact matches

Images from the Hubble Space Telescope reveal a Jupiter - sized planet, perhaps with a surrounding dust disk, orbiting about 115 astronomical units from a nearby main sequence star.

This is much closer to the star than the dust discs of other main - sequence stars with excess far - infrared radiation.

In the original work by Brown, slightly different classes of false positives were used: MPU (main - sequence star with a giant planet); MSU (undiluted binaries); and the two types of diluted binaries, MSDF (an eclipsing binary + a third non-related star) and MSDT (triple systems).

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.

This star is a main sequence, orange - red or red dwarf (K7 - M0 Vp), with peculiar metal - weak spectrum for CA I, CA II, and CR triplet (Christopher J. Corbally, S.J., 1984).

Recently, Hallinan et al. (2015) reported simultaneous radio and optical spectroscopic observations (obtained with the Karl G. Jansky Very Large Array (VLA) radio telescope and the Double Spectrograph (DBSP) on the 5.1 - m Hale telescope, respectively) of auroral emissions of an object at the end of the stellar main sequence (i.e. at the boundary between stars and brown dwarfs).

The internal structures of giant planets are much less well known than those of main - sequence stars because of uncertainties in the equation of state of degenerate gas, the composition (typically non-solar), the interaction with the magnetic field and, in the upper layers, the relative magnitudes of internal heat and energy deposited from the sun.

Depending on a main sequence star's spectral type, even a planet with Earth's atmospheric composition may be colored differently.

Tiny it may be, but 145,000 main sequence stars fill that view, providing us with a gargantuan amount of transit data for hundreds of exoplanets.

Star A is a yellowish main sequence dwarf star of spectral and luminosity type F8 V, with 1.31 times the mass of Sol (McArthur et al, 2010), 1.6 times its diameter, and 3.4 times its luminosStar A is a yellowish main sequence dwarf star of spectral and luminosity type F8 V, with 1.31 times the mass of Sol (McArthur et al, 2010), 1.6 times its diameter, and 3.4 times its luminosstar of spectral and luminosity type F8 V, with 1.31 times the mass of Sol (McArthur et al, 2010), 1.6 times its diameter, and 3.4 times its luminosity.

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.

We use the low overall false positive rate among Kepler multis, together with analysis of Kepler spacecraft and ground - based data, to validate the closely - packed Kepler - 33 planetary system, which orbits a star that has evolved somewhat off of the main sequence.

With the idea of developing strong science cases for a future visible interferometer, we organized a science group around the following topics: pre-main sequence and main sequence stars, fundamental parameters, asteroseismology and classical pulsating stars, evolved stars, massive stars, active galactic nuclei (AGNs) and imaging techniques.

Pre-main-sequence stars of low mass first appear as visible objects, T Tauri stars, with sizes that are several times their ultimate main - sequence sizes.

In high mass main sequence stars, the opacity is dominated by electron scattering, which is nearly constant with increasing temperature.

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 an example, there are stars that have a very low abundance of elements with higher atomic numbers than helium — known as metal - poor stars — that lie just below the main sequence.

In addition to variations in chemical composition — both because of the initial abundances and the star's evolutionary status, [34] interaction with a close companion, [35] rapid rotation, [36] or a magnetic field can also change a main sequence star's position slightly on the HR diagram, to name just a few factors.

61 Virginis is a yellow - orange main sequence dwarf of spectral and luminosity type G5 - 6 V, with about 92 to 96 percent of Sol's mass (95 percent using the isochrone mass estimate of Valenti and Fischer, 2005; and NASA Star and Exoplanet Database, based on David F. Gray, 1992), 94 to 98 percent of its diameter (96 percent for Valenti and Fischer, 2005; Johnson and Wright, 1983, page 677; and NASA Star and Exoplanet Database, derived from the exponential formula of Kenneth R. Lang, 1980), and around 78 percent of its visual luminosity and nearly 81 percent of its theoretical bolometric luminosity, with infrared radiation (Sousa et al, 2008; Valenti and Fischer, 2005; NASA Star and Exoplanet Database, based on Kenneth R. Lang, 1980).

Two of these candidates are common proper motion companions to nearby main sequence stars; if confirmed as binaries, these would be rare benchmark systems with the potential to stringently test ultracool evolutionary models.

We find that 16.5 + / - 3.6 % of main - sequence FGK stars have at least one planet between 0.8 and 1.25 Earth radii with orbital periods up to 85 days.

It is a solar - like main - sequence star with a similar yellowish colour, [31] whose stellar classification is spectral type G2 V. From the determined mutual orbital parameters, Alpha Centauri A is about 10 percent more massive than the Sun, with a radius about 22 percent larger.

The primary, component A, is a Sun - like star [10] with a stellar classification of F8 V, [5] indicating it is an F - type main - sequence star that is generating energy via hydrogen fusion at its core.

We present new high - contrast data obtained during the commissioning of the SPHERE instrument at... ▽ More GJ758 B is a brown dwarf companion to a nearby (15.76 pc) solar - type, metal - rich (M / H = +0.2 dex) main - sequence star (G9V) that was discovered with Subaru / HiCIAO in 2009.

Abstract: GJ758 B is a brown dwarf companion to a nearby (15.76 pc) solar - type, metal - rich (M / H = +0.2 dex) main - sequence star (G9V) that was discovered with Subaru / HiCIAO in 2009.

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.

In about five billion years, our own Sun will make the transition from a main - sequence yellow dwarf star, to a red giant, with dramatic implications for Earth.

An Algol system contains a hot, blue, main sequence star, along with a cool, orange / red star that is more active than our Sun.

Star «B» is a red main sequence dwarf star of spectral and luminosity type M2 V, with about one fifth of Sol's mass, 58 percent of its diameter, and 84/10, 000 th of its luminosStar «B» is a red main sequence dwarf star of spectral and luminosity type M2 V, with about one fifth of Sol's mass, 58 percent of its diameter, and 84/10, 000 th of its luminosstar of spectral and luminosity type M2 V, with about one fifth of Sol's mass, 58 percent of its diameter, and 84/10, 000 th of its luminosity.

This star is a yellow - orange main sequence dwarf star of spectral and luminosity type G0 V, with roughly the same mass as Sol (Irwin et al, 1992), as much as 1.45 times its diameter (George G. Gatewood, 1994, page 143), and less than 1.1 times its luminosity.

From a transit - based estimate of the host star's mean density, combined with analysis of high - resolution spectra, we infer that the host star is near turnoff from the main sequence, with estimated mass and radius of 1.223 (+0.053 -0.091) solar masses and 1.487 (+0.071 -0.084) solar radii.

[5] The secondary star is a K - type main - sequence star that is 0.79 times as massive as the Sun, and with a surface temperature of 4,780 K. [3]

As a star that has evolved out of the «main sequence,» Gacrux has shifted fully from the fusion of hydrogen to helium at its core to the fusion of helium to carbon and oxygen, with trace activity of other nuclear processes.

Its mass and diameter are consistent with the theoretical size for a carbon - core white dwarf, one that may have evolved from a 5.05 +0.374 / -0.276 Solar - mass, B - type main - sequence star about 124 + / - 5 million years ago, after 101 to 126 million years as a giant star (Liebert et al, 2005; and Ken Croswell, 2005).

In March 2005, astronomers seeking ancient stars announced the discovery of HE 1327 - 2326, a subgiant or main - sequence dwarf star with extremely low metallicity — an iron abundance -LRB-[Fe / H] = -5.4 + / - 0.2) that is only about 1/250, 000 th of Sol's and a factor of two lower than that of giant star HE 0107 - 5240 (which is discussed in detail below).

This star is a white - yellow main sequence dwarf star of spectral and luminosity type F6 V, with almost 1.3 times Sol's mass (NASA Star and Exoplanet Database; and David F. Gray, 1992), 1.2 5o 1.3 times its diameter (von Belle and von Braun, 2009, HD 30652 in Table 4, page 7; Perrin and Karoji, 1987; NASA Star and Exoplanet Database; and Kenneth R. Lang, 1980), and over 2.6 times of its bolometric luminosity (NASA Star and Exoplanet Database; and Kenneth R. Lang, 19star is a white - yellow main sequence dwarf star of spectral and luminosity type F6 V, with almost 1.3 times Sol's mass (NASA Star and Exoplanet Database; and David F. Gray, 1992), 1.2 5o 1.3 times its diameter (von Belle and von Braun, 2009, HD 30652 in Table 4, page 7; Perrin and Karoji, 1987; NASA Star and Exoplanet Database; and Kenneth R. Lang, 1980), and over 2.6 times of its bolometric luminosity (NASA Star and Exoplanet Database; and Kenneth R. Lang, 19star of spectral and luminosity type F6 V, with almost 1.3 times Sol's mass (NASA Star and Exoplanet Database; and David F. Gray, 1992), 1.2 5o 1.3 times its diameter (von Belle and von Braun, 2009, HD 30652 in Table 4, page 7; Perrin and Karoji, 1987; NASA Star and Exoplanet Database; and Kenneth R. Lang, 1980), and over 2.6 times of its bolometric luminosity (NASA Star and Exoplanet Database; and Kenneth R. Lang, 19Star and Exoplanet Database; and David F. Gray, 1992), 1.2 5o 1.3 times its diameter (von Belle and von Braun, 2009, HD 30652 in Table 4, page 7; Perrin and Karoji, 1987; NASA Star and Exoplanet Database; and Kenneth R. Lang, 1980), and over 2.6 times of its bolometric luminosity (NASA Star and Exoplanet Database; and Kenneth R. Lang, 19Star and Exoplanet Database; and Kenneth R. Lang, 1980), and over 2.6 times of its bolometric luminosity (NASA Star and Exoplanet Database; and Kenneth R. Lang, 19Star and Exoplanet Database; and Kenneth R. Lang, 1980).

For each star, we made a cross-identification to the Kepler Input Catalog58 (KIC) and restricted the analysis to stars on the main sequence with effective temperatures between 5,100 and 6,000 K (the same range as used by Shibayama et al. 16).

Given the short life of massive B - type stars, it is highly unlikely that an Earth - type planet with advanced multi-cellular life could have developed in Gacrux's water zone before it left the main sequence.

Abstract: Photometric observations made by the NASA Kepler Mission have led to a dramatic increase in the number of main - sequence and subgiant stars with detected solar - like oscillations.

The star may be an orange - red, main sequence dwarf of spectral and luminosity type K2 - 3 V and have an orbital period with Star Ba or 2.2 to 2.9 yestar may be an orange - red, main sequence dwarf of spectral and luminosity type K2 - 3 V and have an orbital period with Star Ba or 2.2 to 2.9 yeStar Ba or 2.2 to 2.9 years.

Massive yet non-supergiant entities known as «Be stars» are main - sequence stars that notably have, or had at some time, one or more Balmer lines in emission, with the hydrogen - related electromagnetic radiation series projected out by the stars being of particular interest.

As a star that has evolved out of the «main sequence,» Arcturus has fully shifted from the fusion of hydrogen to helium in at its core to the fusion of helium to carbon and oxygen, with trace activity of other nuclear processes.

Today for main - sequence stars, the B - class is instead defined by the intensity of the He I violet spectrum, with the maximum intensity corresponding to class B2.

With over 40 Solar - masses, extremely high luminosity, a variable spectra, and surrounding ejecta, it is classified as a Luminous Blue Variable like Eta Carinae, as an extremely large star that are now often regarded as the evolutionary link between main - sequence O stars and the more evolved, smaller but similarly explosive, Wolf - Rayet stars.

After we have calculated the S indices for the 5,648 main - sequence stars based on the LAMOST spectra with signal - to - noise ratios higher than 10 in the blue part of the spectrum, including the subset of 48 superflare stars, it is possible to calculate the flare rates.