A group of researchers that has spent two decades using the radial velocity technique to search for exoplanets has discovered over 100 potential planets and publicized its data online for use by others interested in joining the search.
One of the most successful planet detection techniques, radial velocity uses sophisticated instruments to measure the minuscule gravitational influence an orbiting planet has on its parent star.
For 20 years, scientists have used the HIRES spectrometer on the Keck-I telescope at Hawaii’s W.M. Keck Observatory on Mauna Kea to hunt for planets via the radial velocity method.
Their studies have produced nearly 61,000 measurements of more than 1,600 stars, all of which have now been made public and are available for download from their website.
A separate website describes how to use the open source software program Systemic to search the data for possible planets.
Among the 100 potential planets found is one that orbits a star just 8.1 light years from Earth, making it the fourth closest star system to our own.
That star, known as GJ 411 or Lalande 21185, is low-mass, with about 40 percent the mass of the Sun. Dubbed GJ 411b, the suspected small planet orbits the star every 10 days.
More than 20 years of research have shown that the smallest planets are typically found orbiting the smallest stars.
The international research team published their findings in The Astronomical Journal.
“We were very conservative in this paper about what counts as an exoplanet candidate and what does not,” said Mikko Tuomi of the University of Hertfordshire, who led an analysis of the data in an effort to determine which of the findings are likely to indicate the presence of planets.
“Even with our stringent criteria, we found over 100 new likely planet candidates.”