The Magellan Planet Search Program is a ground-based search for extrasolar planets that makes use of the

radial velocity The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the rate of change of the distance or range between the two points. It is equivalent to the vector projection ...

method. It began gathering data in December 2002 using th
MIKE
echelle spectrograph mounted on the 6.5m Magellan II "Clay" telescope located within the

Las Campanas Observatory Las Campanas Observatory (LCO) is an astronomical observatory owned and operated by the Carnegie Institution for Science (CIS). It is in the southern Atacama Desert of Chile in the Atacama Region approximately northeast of the city of La Serena. ...

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

. In 2010, the program began using the newly commissione
Planet Finder Spectrograph
(PFS), an instrument purpose-built for precise radial velocity measurement.

Specifications

The Magellan Planet Search uses a molecular

Iodine Iodine is a chemical element with the Symbol (chemistry), symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , ...

absorption cell to imprint a set of extremely well known

absorption lines A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identif ...

onto each stellar spectrum that act as a fiducial wavelength reference. In the early years of the program, MIKE spectra were collected with a resolving power, R, of about 65,000 and achieved velocity precision of several meters per second. Using PFS, most spectra are collected with a resolving power of about 80,000 and velocity precision closer to one meter per second.

Observations

The program has surveyed approximately 500

star A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make ...

s with spectral types ranging from F7 to M5. Stars included in the program were initially chosen to minimize overlap with two complementary surveys: the Anglo-Australian Planet Search (AAT) and the Keck Hi-Res planet search. The Magellan Planet Search has discovered a number of extrasolar planets using MIKE data alone, PFS data alone, a combination of the two, and a combination of these and data collected using other telescopes and instruments. For example, an early announcement was made in January 2010 regarding the discovery of five long period, Jovian mass planets in eccentric orbits around G and K type dwarfs.

Extrasolar planets discovered

As of December 2013, the program had announced the following discoveries: :* HD 48265 b :* HD 86226 b :* HD 129445 b :* HD 143361 b :* HD 152079 b :*

HD 164604 b HD 164604 b is an extrasolar planet discovered in January 2010 in association with the Magellan Planet Search Program. It has a minimum mass 2.7 times the mass of Jupiter and an orbital period of 606.4 days. Its star is classified as a K2 V dwarf ...

:* HD 175167 b :* HD 28185 b :*

HD 111232 b HD 111232 b is an extrasolar planet that orbits at almost 2 AU with a minimum mass of 6.8 times that of Jupiter. This planet was discovered in the La Silla Observatory by Michel Mayor using the CORALIE spectrograph on 30 June 2003, along with six ...

HD 106906 b HD 106906 b is a directly imaged planetary-mass companion and candidate exoplanet orbiting the star , in the constellation Crux at about from Earth. It is estimated to be about eleven times the mass of Jupiter and is located about 738 AU ...

References

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