http://www.astronomy.com/news/2013/10/a-strange-lonely-planet-found-without-a-star
October 10, 2013 - Astronomy.com
An international team of astronomers has discovered an exotic young
planet that is not orbiting a star. This free-floating planet, PSO
J318.5-22, is just 80 light-years away from Earth and has a mass only
six times that of Jupiter. The planet formed a mere 12 million years ago
— a newborn in planet lifetimes.
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The team followed up the PS1 discovery with multiple telescopes on the
summit of Mauna Kea on the island of Hawaii. Infrared spectra taken with
the NASA Infrared Telescope Facility and the Gemini North Telescope
showed that PSO J318.5-22 was not a brown dwarf, based on signatures in
its infrared light that are best explained by it being young and
low-mass.
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