Georg August University of Göttingen | 2020 Jun 25
International researchers led by University of Göttingen find multiple planet system orbiting Gliese 887
The nearest exoplanets to us provide the best opportunities for detailed study, including searching for evidence of life outside the Solar System. In research led by the University of Göttingen, the RedDots team of astronomers has detected a system of super-Earth planets orbiting the nearby star Gliese 887, the brightest red dwarf star in the sky. Super-Earths are planets which have a mass higher than the Earth’s but substantially below those of our local ice giants, Uranus and Neptune. The newly discovered super-Earths lie close to the red dwarf’s habitable zone, where water can exist in liquid form, and could be rocky worlds. ...
The RedDots team of astronomers monitored the red dwarf, using the HARPS spectrograph at the European Southern Observatory in Chile. They used a technique known as “Doppler wobble”, which enables them to measure the tiny back and forth wobbles of the star caused by the gravitational pull of the planets. The regular signals correspond to orbits of just 9.3 and 21.8 days, indicating two super-Earths – Gliese 887b and Gliese 887c – both larger than the Earth yet moving rapidly, much faster even than Mercury. Scientists estimate the temperature of Gliese 887c to be around 70°C.
A Multiple Planet System of Super-Earths Orbiting
the Brightest Red Dwarf Star GJ 887 ~ Sandra Jeffers et al
- Science 368(6498):1477 (26 Jun 2020) DOI: 10.1126/science.aaz0795