Eight More Huge Extrasolar Planets Found

July 8, 2003

Discoveries of planets around other stars continue to build, with the total of known extrasolar planets around normal stars reaching 117 in recent weeks.

A European planet-hunting team, led by Michel Mayor of the Geneva Observatory, announced seven new discoveries on June 30, though the findings were not widely reported. The planets' masses range from about one to eight times that of Jupiter. Their orbits range in length from roughly one to four Earth-years. A pair of the newfound planets orbits the same star, called HD 169830.

In addition, a Japanese team detected a planet six times the mass of Jupiter orbiting the star HD 104985, which was previously found to host another planet.

There are now 13 known multiple-planet systems beyond our own.

The most recent announcement, reported July 3, revealed a Jupiter-like planet in a rare circular orbit roughly 3.3 times as far from its star as Earth is from the Sun. This discovery is one of two over the past 13 months involving stable Jovian-like orbits that raise hopes for finding solar systems similar to our own complete with Earth-like planets.

None of the planets found around normal stars so far are small enough to be rocky, like Earth. However, an additional planet system exists around a dying, fast-spinning star called a pulsar. The three planets around PSR 1257+12 are all roughly Earth-sized, but they're not thought to be habitable.

Counting these so-called pulsar planets -- some astronomers prefer not to -- the total tally of exoplanets now stands at 120, and there are 14 multiple-planet systems.

-- Robert Roy Britt

History of Flight Fact: On this date in 1940, the Boeing Stratoliner, the first airliner with a pressurized cabin had its maiden voyage. The new design allowed the plane to fly up to 20,000 feet, avoiding turbulence

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