Standard Type Ia supernovae are binary systems in which a white dwarf star draws so much matter from its companion (often a red giant) that it undergoes a kind of energy overload and detonates.

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Most stars in the galaxy are, in fact, in binary systems, and astronomers have been wondering whether the gravity of a second star nearby might disrupt a dust disc too much for planets to coalesce.

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This theory seemed to agree with observations taken over the last three decades, which reveal that binary systems are abundant, but none of the pairs have an orbital period shorter than five hours, the researchers said.

MSN: 'Impossible' stars found in our galaxy - Technology & science - Space - Space.com | NBC News

But many stars are partnered in binary star systems.

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Secondly, the detection of multiple planets demolishes once and for all the lingering doubts of some astronomers that the single planets found around other stars are not planets at all, but small, faint components in otherwise conventional binary star systems.

ECONOMIST: Planet hunting

The discovery of exoplanets in binary and triple-star systems raises the prospect that the galaxy houses many more such objects than was previously thought.

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