Amateurs Help Discover a Planet that Might be a Brown Dwarf

Another new planet has been announced this week that crosses the line between planet and brown dwarf. This time, the planet is called XO-3b, and it was discovered through a collaboration between amateur and professional astronomers.

XO-3b contains 13 times the mass of Jupiter, and orbits its parent star every 4 days. It was first discovered using a low budget telescope, part of the XO project, located on the Haleakala summit on Maui, Hawaii. The telescope is actually made up of two commercially available 200-millimetre telephoto lenses which watch stars for the characteristic dimming as a planet passes in front. When a suspected transit is seen, larger telescopes are brought in to confirm the findings.

Brown dwarfs are failed stars, lacking the mass to ignite fusion, but they do have enough mass to fuse deuterium. Astronomers categorized them as any object between 13 and 80 times the mass of Jupiter. With 13-Jupiter masses, XO-3b sits right at the dividing line between planet and brown dwarf.

Original Source: Rice University News Release