HD 8574 B - Discovery

Discovery

The ELODIE Planet Search Survey, undertaken using the ELODIE spectrograph at the Haute-Provence Observatory in southeastern France, was a large-scale search for extrasolar planets orbiting G-type and F-type dwarf stars visible from the Northern Hemisphere through use of the radial velocity method (the orbit of a planet tugs on its host star as it orbits, causing a perceived Doppler effect in the star's spectrum). This survey, which started in 1994, led to the discovery of 51 Pegasi b, the first extrasolar planet discovered in the orbit of a sunlike star. By 2003, the discovery of six new planets, including HD 8574 b, was announced, bringing ELODIE's planet discovery count to eighteen.

HD 8574, one of the target stars of ELODIE, had been previously catalogued by the European Space Agency with the release of the Hipparcos catalogue in 1997. Most of HD 8574's characteristics were extracted from this catalogue for use in searching for a planet around HD 8574. The spectrum was then analyzed to see if HD 8574 were active, a factor that could mask or mimic the signal of an orbiting planet. It was found that the star was not significantly active.

In the case of HD 8574, ELODIE obtained 41 radial velocity measurements, which had, at the time of the discovery paper, been collected since January 11, 1998. Analysis of the collected data confirmed the existence of a planet orbiting HD 8574. Of the six, the planet HD 8574 b had the shortest orbital period, orbiting its host star under three years (unlike the five other planets that had been discovered by ELODIE at the same time).

HD 8574 b was announced by the European Southern Observatory on April 4, 2001. The findings addressing HD 8574's discovery were published in 2003.