Scientists at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., used the National Aeronautics and Space Administration's Spitzer Space Telescope to study a huge belt of warm dust swirling around a distant star that's slightly more massive than the sun.

The dust belt, which the APL astronomers said they suspect is clumping into planets, is located in the middle of the system's terrestrial habitable zone -- an area in which liquid water could exist. Earth is located in the middle of the sun's terrestrial habitable zone.

"The timing for this system to be building an Earth is very good," said Carey Lisse of APL. "It is fantastic to think we are able to detect the process of terrestrial planet formation. Stay tuned -- I expect lots more fireworks as the planet in HD113766 grows."

A report by Lisse on the research is to appear in an upcoming issue of the Astrophysical Journal.