Stars or Planets? It Depends
A newly spotted pair of planet-sized objects floating far away from any star has astronomers puzzling over how such a bizarre system could have formed.
Using the European Southern Observatory's telescopes in Chile, astronomers have spotted a seven-Jupiter mass object paired to another 14-Jupiter-mass companion. Instead of orbiting around a star, however, the two planetary mass objects, or "planemos," are circling each other.
Planemos are objects similar to brown dwarfs, failed stars too small to sustain the nuclear reactions required for stellar ignition. But at only a few times more massive than Jupiter, they resemble planets more than stars.
Technically, at 14 times the mass of Jupiter, the larger of these objects could qualify as a mini-star in some classification schemes. The article goes on to explain that an object that achieves 13 times the mass of Jupiter can go through a deuterium-burning stage early on -- making it a very brief, cool star. But the question of planethood apparently doesn't rest entirely with mass. There's also the question of how these objects were formed.
The bottom line is that they're too small to be out there on there own, at least according to the way we normally figure this stuff. So were they once attached to a larger star or stars? And if so, what happened?
