Sentences with phrase «radial velocities of»

He then relates what drove the development of a spectrograph called ELODIE, designed to offer very high sensitivity in measuring the radial velocities of stars.

Abstract: We have constructed a thermally compensated field - widened monolithic Michelson interferometer that can be used with a medium - resolution spectrograph to measure precise Doppler radial velocities of stars.

[18] The internal dynamics have been analyzed using measurements of the radial velocities of 469 stars.

HARPS allows for measurements of radial velocities of stars, which can be affected by the presence of nearby planets, to be taken with the highest accuracy currently available.

Meanwhile, a study to be published in Astrophysical Bulletin that used just the radial velocities of stars found, similar to Moni Bidin's team, that much less dark matter than expected was required to explain the motions of stars in the local universe.

They then calculated the size, position and mass of K2 - 229b by measuring the radial velocity of the star, and finding out how much the starlight «wobbles» during orbit, due to the gravitational tug from the planet, which changes depending on the planet's size.

In 1947, Alfred H. Joy (page 101) reported finding that Groombridge 34 A had an observed range in the radial velocity of 26 km / sec and so may be a spectroscopic binary star.

In addition to the orbital motion caused by the transiting planet, we detect a possible linear trend in the radial velocity of KELT - 22A suggesting the presence of another relatively nearby body that is perhaps non-stellar.

From these readings, the radial velocity of the parent star relative to the Earth is varying with an amplitude of about 2 metres (6.6 ft) per second.

[12] HD 119124 is moving closer to the Sun with a radial velocity of − 12 km / s.

If the angular distance of a star from the radiant is λ and if the velocity of the cluster as a whole with respect to the Sun is V, then the radial velocity of the star, Vr, is Vr = V cos λ.

According to Robert Burnham, Jr. (1931 - 93), Gacrux has an annual proper motion of 0.27» in PA 175 ° and a radial velocity of 13 miles (21 km) per second in recession.

It is moving away from the Earth with a radial velocity of +35.8 km / s.

We also find a slow variation in the radial velocity of Procyon, with good agreement between different telescopes.

Narrow, stable Ca II and / or Na I absorption features have been detected superimposed to the photospheric lines in 10 out of the 15 observed cold - gas - bearing debris disc.Features are found at the radial velocity of the stars, or slightly blue - or red - shifted, and / or at the velocity of the local interstellar medium (ISM).

According to Robert Burnham, Jr. (1931 - 93), Aldebaran A exhibits an annual proper motion of 0.21» around PA 160 ° with an radial velocity of about 33 miles (53 km) per second in recession.

Not exact matches

[1] Most of the exoplanets currently known were discovered using indirect techniques — such as radial velocity variations of the host star, or the dip in brightness of the star caused by a transiting exoplanet.

The planet was found with the radial velocity method, a planet - hunting technique that relies upon slight variations in the velocity of a star to determine the gravitational pull exerted by nearby planets that are too faint to observe directly with a telescope.

These will include planet - hunting stalwarts such as the HARPS instrument at the European Southern Observatory in La Silla, Chile, and the new Miniature Exoplanet Radial Velocity Array (MINERVA)- Australis, a group of five planned 0.7 - metre telescopes near Toowoomba, Australia.

[2] The team looked at radial velocity data of Gliese 667C, a method often used to hunt for exoplanets.

[1] The team used data from the UVES spectrograph on ESO's Very Large Telescope in Chile (to determine the properties of the star accurately), the Carnegie Planet Finder Spectrograph (PFS) at the 6.5 - metre Magellan II Telescope at the Las Campanas Observatory in Chile, the HIRES spectrograph mounted on the Keck 10 - metre telescope on Mauna Kea, Hawaii as well as extensive previous data from HARPS (the High Accuracy Radial velocity Planet Searcher) at ESO's 3.6 - metre telescope in Chile (gathered through the M dwarf programme led by X. Bonfils and M. Mayor 2003 - 2010.

A ground - based telescope in Chile discovered 55 of these planets, including HD 85512b, using an instrument called the High Accuracy Radial Velocity Planets Searcher (HARPS).

Instead of becoming an Earth - shattering revelation, serious doubts were cast on the detection, which also used radial velocity.

Using the European Southern Observatory's High Accuracy Radial velocity Planet Searcher instrument in Chile, researchers detected a slight wobble in the position of a star called Ross 128, indicative of an orbiting planet.

And radial velocity searches, which look for Doppler shifts in a star's light as it wobbles under the influence of an orbiting companion, are more attuned to massive planets that induce greater gravitational wobbles in their host stars.

«We designed an experiment to confirm what we suspected was there,» says team leader Guillem Anglada - Escudé of Queen Mary University of London, who used the European Southern Observatory's High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph on a 3.6 - meter telescope in Chile.

Teasing out the subtle signature of small planets in radial - velocity data takes a wealth of observations, especially when the signal is dominated by larger planets in the system, and others are sure to investigate whether the signature of Gliese 581g is real.

«These data recover the well - known solar 5 - minute oscillation at a peak of 3 mHz (5.5 min) from the disk - averaged light with a radial - velocity amplitude of only 47 cm / s, an incredibly small velocity from a stellar point of view», says Prof. Strassmeier, PEPSI principal investigator and director of the Cosmic Magnetic Field branch at the Leibniz Institute for Astrophysics Potsdam (AIP).

The results of follow - up observations (see Table 2) are a mixture of results from photometric follow - up (Deeg et al. 2009), which identifies contaminating» diluted EB's that are more than about 2 distant from the third star - which usually coincides with the observing target -, and from spectroscopic (radial velocity) results, which can only identify signals from sources that fall into the spectrograph's entry slit; that is, they have to be very close (less than 1 - 2) to the target.

As part of a large survey of possible planet - hosting stars, Lovis and his colleagues used the powerful HARPS (for High Accuracy Radial - Velocity Planet Searcher) spectrograph at La Silla Observatory in Chile, 2,400 meters above sea level, which can detect stellar motions with precisions of less than one meter per second, roughly the walking speed of a human being.

The radial - velocity variations indicate a highly eccentric orbit with a period of 153.9 days.

The new discoveries were made with the help of the radial velocity method, which looks for the periodic shifts of certain spectral lines in a star's light that are caused by the gravitational tug of invisible planets which orbit the star.

Due to the close binary orbital interactions of the host star with Alpha Centauri A and Star B's own increased stellar activity during recent years, the astronomers were only able to detect the radial - velocity variations of host star B that were caused by the 3.236 - day orbit of the planet (with a semi-major axis of 0.04 AU) only after more than four and a half years of careful observation.

On October 16, 2012, a team of astronomers announced the discovery of a planet with around 1.13 + / - 0.09 Earth - masses in a very hot and tight, circular orbit around Alpha Centauri B, using the European Southern Observatory's the High Accuracy Radial velocity Planet Searcher (HARPS) instrument on the 3.6 - metre telescope at ESO's La Silla Observatory in Chile.

Therefore, the radial velocity surveys only pick the lowest hanging fruit: Jupiters that have migrated close in to their star, and have orbital periods of literally only a few days.

Planet «b» - In 1996, a team of astronomers (including Eric Williams, Heather M. Hauser, and Phil Shirts) led by Geoffrey W. Marcy and R. Paul Butler announced the discovery of a Jupiter - class planet around Upsilon Andromedae (ups And) A using highly sensitive radial - velocity methods (Butler and Marcy, 1997.

The failure, thus far, to find large substellar objects like brown dwarfs or a Jupiter - or Saturn - class planet in a «torch» orbit (closer han the Mercury to Sun distance) around 107 Piscium — with even the highly sensitive radial - velocity technique of Geoffrey W. Marcy and R. Paul Butler — bodes well for the possibility of Earth - type terrestrial planets around this star (Cumming et al, 1999).

The method used to detect carbon monoxide utilized the radial velocity (RV) technique — a technique commonly used in the visible region of the spectrum, to which our eyes are sensitive — for discovering non-transiting exoplanets.

In July 2008, astronomers (Michael Endl and Martin Kürster) analyzed used seven years of differential radial velocity measurements for Proxima Centauri to submit a paper indicating that large planets are unlikely to be orbiting Sol's closest stellar neighbor within its habitable zone — around 0.022 to 0.054 AU with a corresponding orbital period of 3.6 to 13.8 days.

Planet «c» - A residual drift in the radial velocity data over a decade suggest the presence of even larger planets in outer orbits (Butler et al, 1999).

Still, many of the nearby planets are detectable via three exoplanet hunting methods: planetary transits, high - contrast imaging, and stellar radial velocity measurements.

G.D., V.B., S.C.N., M.T.D., T.E., C.G., H.J. - C., D.H.K., A.F., J.G., A.I., J.F.K., M.M., K.M., N.N., T.E.O., P.A.R., G.S., D.C.S., R.R.Y., R.Z., B.J.F. and A.H. all provided photometric or radial velocity data that were important for the interpretation of the system.

The study culminates many years of effort by an international team of scientists who have discovered a large number of the satellite galaxies, developed new techniques to measure their distances, and have used the Keck Observatory with colleagues to measure their radial velocities, or Doppler shifts (the speed of the galaxy relative to the Sun).

It appears to be a main sequence red dwarf star of spectral and luminosity type M4.5 V. Because of its small mass and great distance from the primary (Star A), Upsilon Andromedae B appears to have a negligible effect on the radial velocity measurements used to determine that Star A has at least three large planets (Lowrance et al, 2002).

On October 16, 2012, a team of astronomers announced the discovery of a planet with around 1.13 + / - 0.09 Earth - masses in a very hot and tight, circular orbit around Alpha Centauri B, using the European Southern Observatory's High Accuracy Radial velocity Planet Searcher (HARPS) instrument on the 3.6 - metre telescope at ESO's La Silla Observatory in Chile.

Abstract: We report the discovery of a low - mass companion orbiting the metal - rich, main sequence F star TYC 2949 -00557-1 during the MARVELS (Multi-object APO Radial Velocity Exoplanet Large - area Survey) Pilot Project.

For low - mass eclipsing binary stars, the method of eclipse minimum timing allows astronomers to search for smaller masses than those feasible with radial velocity measurements.

Even though the radial velocity method can only give some rough measurements of an exoplanet's properties, like minimum mass and orbital period, it nevertheless allows astronomers to make some educated guesses regarding the planet's overall structure.

«Results from the three main techniques of planet detection (radial velocity, transit and microlensing techniques) are rapidly converging to a common result: Not only are planets common in the galaxy, but there are more small planets than large ones,» said Stephen Kane, of NASA's Exoplanet Science Institute at the California Institute of Technology, Pasadena, Calif. «This is encouraging news for investigations into habitable planets.»

Measurements of Gl 105A's radial velocity over 12 years show a linear trend and slope which is consistent with these orbital constraints and a nearly face - on orbit.