Our Closest Star System

Astronomer Kevin Luhman announced the discover of the binary brown stars WISE 1049-5319 (full designation name WISE J104915.57-531906) making them the closest brown stars and star systems to our Solar System. They are just 6.5 lights years from our sun. The pair orbit each other at a distance of about 3 AU[1] with an orbital period of about 25 years. Luhman discovered the brown dwarfs from images made by the Wide-field Infrared Survey Explorer (WISE); the discovery was announced in 2013. Luhman is from Pennsylvania State University and is a researcher in Penn State’s Center for Exoplanets and Habitable Worlds.

WISE 1049-5319 appears in the sky close to the galactic plane which is densely populated by stars; the abundance of light sources makes it difficult to spot faint objects. This explains why an object so near to the Sun was not discovered in earlier searches. The second component of the system was discovered also by Luhman in 2013. Its discovery image in i-band was taken on the night of 23 February 2013 with the Gemini Multi-Object Spectrograph (GMOS) at the Gemini South telescope, Chile.

Brown dwarfs are substellar objects too low in mass to sustain hydrogen-1 fusion reactions in their cores, unlike main-sequence stars, which can. They occupy the mass range between the heaviest gas giants and the lightest stars.