SIX more planets beyond the Solar System have come to light, almost doubling the number discovered to date.
Three teams of astronomers spotted wobbles in six nearby stars. They think the wobbles are caused by orbiting planets with at least half the mass of Jupiter. Most theories about how planets form suggest their orbits should be almost circular. But the orbits of these planets look highly eccentric.
"Astronomers are in a state of confusion as to what constitutes a normal solar system," says Geoff Marcy of the University of California at Berkeley, codiscoverer of one of the planets. He suggests that the gravity of one large planet may fling another into a highly eccentric orbit.
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