In their quest to find solar systems analogous to ours, astronomers have determined how common our solar system is.

They've concluded that about 15 percent of stars in the galaxy host systems of planets like our own, with several gas giant planets in the outer part of the solar system.

Gaudi reported the results of the new study at the American Astronomical Society Meeting in Washington, DC, when he accepted the Helen B. Warner Prize for Astronomy.

The find comes from a worldwide collaboration headquartered at Ohio State called the Microlensing Follow-Up Network (MicroFUN), which searches the sky for extrasolar planets.

MicroFUN astronomers use a method called gravitational microlensing, which occurs when one star happens to cross in front of another as seen from Earth. The nearer star magnifies the light from the more distant star like a lens. If planets are orbiting the lens star, they boost the magnification briefly as they pass by.

This method is especially good at detecting giant planets in the outer reaches of solar systems - planets analogous to our own Jupiter.

This latest MicroFUN result is the culmination of 10 years' work - and one sudden epiphany, explained Gaudi and Andrew Gould, professor of astronomy at Ohio State.

Ten years ago, Gaudi wrote his doctoral thesis on a method for calculating the likelihood that extrasolar planets exist. At the time, he concluded that less than 45 percent of stars could harbor a configuration similar to our own solar system.

"The planets are shown in the correct order of distance from the Sun, the correct relative sizes, and the correct relative orbital distances. The sizes of the bodies are greatly exaggerated relative to the orbital distances. The faint rings of Jupiter, Uranus, and Neptune are not shown. Eris, Haumea, and Makemake do not appear in the illustration owing to their highly tilted orbits. The dwarf planet Ceres is not shown separately; it resides in the asteroid belt between Mars and Jupiter. (Credit: NASA)"

Source: Ohio State University