Astronomers have discovered two super-Earth exoplanets orbiting a star 11 light-years away from Earth, according to a new study. There is also a potential third planet orbiting a bit further away from the star, according to the researchers.
The proximity of this intriguing nearby planetary system will enable it to be studied more in the future, the researchers said.
The star, Gliese 887, is a small, dim red dwarf star with about half the mass of our sun. But given its proximity, it’s the brightest red dwarf in the sky. It’s also one of the closest stars to our sun, even though it’s far from the reach of any spacecraft technology we have today.
A team of astronomers working on the Red Dots project, which is attempting to find terrestrial exoplanets closest to our sun, observed the star using the European Southern Observatory in Chile. The team observed the star every night for three months. The High Accuracy Radial velocity Planet Searcher, known as the HARPS spectrograph, detected two planets around Gliese 887.
The spectrograph was able to detect the planets using a technique astronomers call the “Doppler wobble” or radial velocity method. This so-called wobble occurs when the star moves back and forth due to the gravitational pull of the planets orbiting it. The HARPS instrument can measure these tiny wobbles.