Astronomers have long theorized that there are many planets that have drifted away from their home stars, whether it’s a too-loose gravitational pul
eso1245a – Artist’s impression of the free-floating planet CFBDSIR J214947.2-040308.9. This video shows an artist’s impression of the free-floating planet CFBDSIR J214947.2-040308.9. In the first part of the sequence the planet appears as a dark disc in visible light, silhouetted against the star clouds of the Milky Way. This is the closest such object to the Solar System and the most exciting candidate free-floating planet found so far. It does not orbit a star and hence does not shine by reflected light; the faint glow it emits can only be detected in infrared light. In the final sequence we see an infrared view of the object with the central parts of the Milky Way as seen by the VISTA infrared survey telescope as background. The object appears blueish in this near-infrared view because much of the light at longer infrared wavelengths is absorbed by methane and other molecules in the planet’s atmosphere. In visible light the object is so cool that it would only shine dimly with a deep red colour when seen close-up.