HILO, Hawai'i — Astronomers at two of the world's largest telescopes on Mauna Kea have gathered evidence that suggests the rocky planets and moons of our inner solar system may not be as rare as was once believed.

New research published in the July 21 issue of the British science journal Nature describes warm dust detected around star BD +20 307, which is about 300 light years from the sun in the constellation Aries.

The dust is believed to be caused by recent collisions of rocky objects and has probably surrounded the star for the past 1,000 years or so. If the dust had been there any longer, gravity would have dragged the finest particles, which are about the size of cigarette smoke particles, into the star.

The objects that collided and created the dust around BD +20 307 must have been at least as large as the largest asteroids present today in our solar system, which are about 185 miles across.

The new research is among the earliest efforts to seek out and study "warm dust," which is debris from a cosmic smash-up that lingers close enough to stars to be warmed by the stars' radiant energy, said Inseok Song, the Gemini staff astronomer who led the U.S.-based research team.

That warm dust is exactly what astronomers would expect to see in a solar system similar to our own.

The star BD +20 307 is believed to be about 300 million years old, so any large planets that might orbit it must have already formed, astronomers said.

The new observations by astronomers at the Gemini and W.M. Keck Observatories on Mauna Kea lend support to the idea that similar collisions of rocky bodies occurred early in the formation of our own solar system about 4.5 billion years ago, scientists said.

The new observations also imply solar systems like our own may be more common than some astronomers believed, Song said.

Research on dusty stars over the past 20 years or so mostly focused on "cold dust," or debris farther from the stars, because cold dust is easier to detect, he said.

Studying warm dust is more complicated because scientists somehow had to distinguish between the radiant energy from the star, and the signal from the dust itself, he said.

As new as this area of research is, astronomers have studied several thousand likely candidate stars, and have discovered two stars with warm dust, including BD +20 307, the subject of the Mauna Kea research, Song said.

"If someone carries out systematic searches in a very careful way, then in the future we may be beginning to see more and more of this type of warm dust," which will point to more likely candidates for solar systems like our own, he said.

Correction: The distance from Earth to Star BD +20 307 was incorrect in a previous version of this story.