A team of astronomers has discovered 18 Jupiter-like planets in orbit around massive stars, stated in a press release from the California Institute of Technology.
“It’s the largest single announcement of planets in orbit around stars more massive than the Sun, aside from the discoveries made by the Kepler mission,” said John Johnson, assistant professor of astronomy at the California Institute of Technology and lead author on a paper, published in the Astrophysical Journal Supplement Series.
The Keck Observatory in Hawaii (NASA)
Using the Keck Observatory in Hawaii, with follow-up observations using the McDonald and Fairborn Observatories in Texas and Arizona, respectively, the researchers surveyed about 300 stars. They focused on those dubbed retired A-type stars that are more than one and a half times more massive than the Sun.
To look for planets, the astronomers searched for stars of this type that wobble, which could be caused by the gravitational tug of an orbiting planet. By searching the wobbly stars’ spectra for Doppler shifts – the lengthening and contracting of wavelengths due to motion away from and toward the observer – the team found 18 planets with masses similar to Jupiter’s.
This new bounty marks a 50 percent increase in the number of known planets orbiting massive stars and, according to Johnson, provides an invaluable population of planetary systems for understanding how planets – and our own Solar system – might form. The researchers say that the findings also lend further support to the theory that planets grow from seed particles that accumulate gas and dust in a disk surrounding a newborn star.
