http://www.spacedaily.com/reports/Brown_Dwarf_Found_Orbiting_A_Young_Sun_Like_Star_999.html
Astronomers have imaged a 36 Jupiter-mass very young brown dwarf tightly orbiting a young nearby sun-like star. International astronomers made the rare find using the Near-Infrared Coronagraphic Imager on the international 8-meter Gemini-South Telescope in Chile. The brown dwarf, PZ Tel B, is only 18 astronomical units from the primary star PZ Tel A. Only 18 Astronomical Units separates them, similar to Uranus from the sun.
Most directly imaged young brown dwarf and planetary companions are at orbital separations greater than 50 AU, larger Pluto’s 40 AU orbit. In addition to its small separation, in just the past year PZ Tel B has moved quickly outward from its parent star. A seven-year-old image showed the glare from the host star obscured PZ Tel B.
PZ Tel A is rare being both close and very young, so we imaged it several times in the past. It was surprisingly to see a new companion around what we thought was a single star. PZ Tel B travels on a particularly eccentric orbit. In the last 10 years, it has careen through its inner solar system. We can best explain this by a highly eccentric, oval-shaped orbit rather than circular.
Host star PZ Tel A is like our sun, being of similar mass but only 12 million years old. Our Sun is 400 times older. The PZ Tel system is still young enough to possess significant cold circumstellar dust, which the brown dwarf may have gravitationally sculpted. This makes the system important to study early solar system formation stages. PZ Tel B’s orbital motion has significant implications for what planets can form, and whether they can form at all.
Because PZ Tel B is so close to its parent star, it was difficult to distinguish the faint companion’s light from the primary star. PZ Tel B is only 0.33 arcseconds from PZ Tel A, equivalent to a dime seen from 7 miles. Adaptive optics coupled to a coronagraph to block excess starlight allowed pictures so close to the star. Specialized image analysis techniques detected PZ Tel B and measured its orbital motion.
The Near-Infrared Coronagraphic Imager that discovered PZ Tel B can detect companions a millionth the intensity of the host star at just one arcsecond separation. We are just beginning to learn the many solar system configurations around sun like stars.
I wonder if the Dwarf passes close enough to it's host/companion to have some of it's material siphoned off. If so, the dwarf might eventually become a gas giant planet with a more circular orbit?
Interesting. It's a failed Binary system.
Seems like if there is any material to be siphoned, the host star would get it from the host star. As young as that star is, if we assume it is the same mass as our Sun, it will be more than 10 billion years before it starts ejecting its outter atmosphere for the dwarf to siphon. If the dwarf still exists though, and if it is massive enough now, it might gain enough mass then to idnite as a new star. That's an interesting possibility Dewtey got me considering.
NASA's got some good stuff on this, at the following site: http://rst.gsfc.nasa.gov/Sect20/A5a.html
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