Lightest Exoplanet to Help Astronomers Better Understand Evolution of Planetary Systems: ESO

Astronomers using the European Southern Observatory's Very Large Telescope have reported that they've located a light exoplanet around a bright star. The newly discovered exoplanet is about four to five times the mass of Jupiter. The study team says that the latest findings will help astronomers better understand the evolution of planets.

The new exoplanet is one of the few that have been directly imaged by using the ESO's Very Large Telescope.

"Direct imaging of planets is an extremely challenging technique that requires the most advanced instruments, whether ground-based or in space," said Julien Rameau (Institut de Planetologie et d'Astrophysique de Grenoble, France), first author of the paper announcing the discovery in a news release from the agency. "Only a few planets have been directly observed so far, making every single discovery an important milestone on the road to understanding giant planets and how they form.

Astronomers say that the exoplanet appears as a clear dot near the star HD 95086. Later observations showed that the planet was moving along with the star, which suggests that the planet, called HD 95086 b, is in an orbit around the star.

The star-planet system is about 300 light-years away from us. Also, the planet is about 56 times farther away from its star than the Earth from the Sun.

The star HD 95086 is young, just 10 to 17 million years old. By comparison, our sun is about 4.6 billion years. The newly discovered star has a disc of debris around it, which made it a good candidate for observations.

"Its current location raises questions about its formation process. It either grew by assembling the rocks that form the solid core and then slowly accumulated gas from the environment to form the heavy atmosphere, or started forming from a gaseous clump that arose from gravitational instabilities in the disc." said Anne-Marie Lagrange, co-author of the study. "Interactions between the planet and the disc itself or with other planets may have also moved the planet from where it was born."

The study paper, titled "Discovery of a probable 4-5 Jupiter-mass exoplanet to HD95086 by direct-imaging", will appear in the journal Astrophysical Journal Letters.