The planet, GJ 504b, orbits the sun-like star GJ 504, about 60 light-years from Earth. It was discovered, and imaged, by an international team of astronomers using the Subaru Telescope in Hawaii. It has been referred to as a “second Jupiter” and has an estimated mass of about three Jupiters, orbiting its star at a distance farther than Neptune in our own solar system. If the calculated mass is accurate, it would be the lightest exoplanet directly imaged so far.
The discovery was part of the Strategic Explorations of Exoplanets and Disks with Subaru (SEEDS) Project.
Despite its size, it is still much fainter than its star, and so still only appears as a point of light. However, the astronomers were still able to analyze its reflected light, determining that it is more bluish in colour than other exoplanets imaged previously. This tells scientists that its atmosphere is probably less cloudy as well. Some reports describe the planet’s colour as actually more magenta; according to researcher Michael McElwain, of NASA’s Goddard Space Flight Center in Greenbelt, Md. (via Space.com), “If we could travel to this giant planet, we would see a world still glowing from the heat of its formation with a color reminiscent of a dark cherry blossom, a dull magenta.”
The discovery bodes well for being able to directly image Earth-sized planets in the future as the technology continues to improve.A growing number of such worlds have already been discovered using other techniques, but being able to actually see a planet similar in size (and perhaps other ways as well) to our own in another solar system would be exciting indeed.
The new findings will be published in The Astrophysical Journal.