Astronomers have found a planetary system circling a Sun-like star 127 light-years away. The system has five firmly established planets, plus two more likely ones. All five of the firm planets have masses similar to Neptune, but they orbit their star close in, closer than Mars' orbit around the Sun. With five masses of that size orbiting so comparatively close to each other, the long term stability of that arrangement might be open to question.
The most interesting worlds in the system, however, might be the two not completely nailed down yet. One seems to have the mass of Saturn and orbits the star at a distance roughly comparable to Saturn's distance from the Sun. The second likely seems to be only a bit more massive than Earth-- which would make it the smallest exoplanet yet discovered-- but it orbits its star twice in about three of our days. No Earth-like life there.
All these worlds were discovered by noting "wobbles" in the star caused by the gravity of planets tugging it this way and that. The prrocess is laborious and time-consuming, but it works.
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