PASADENA, CALIF -- Huge, cold, lonely and of fuzzy origin, brown dwarfs came into significantly sharper focus today when researchers announced that the failed stars with the strange name may harbor planets, a privilege previously reserved for real stars.

The finding raises hopes for a planet, albeit a frigid and dark world, orbiting a brown dwarf near our Solar System.

The evidence came in the form of dust disks found around a host of brown dwarfs. These objects are typically 10 to 70 times more massive than Jupiter and are similar to stars but never had enough mass to trigger the thermonuclear fusion that powers a real star. The brown dwarfs in the study are free-floating, meaning they do not orbit another star.

If brown dwarfs, even those on the low end of the range of mass for these objects, have planets around them, now there is no question that brown dwarfs form as stars do.

The debris disks strongly indicate that these free-floating brown dwarfs formed in the same way other stars form, in the gravitational collapse of a cloud of gas and dust. The findings were presented here Thursday at an American Astronomical Society meeting.

The new research also raises questions about the distinction between brown dwarfs and other free-floating interstellar objects that some researchers recently have identified and quibbled over. Those objects, less massive than most brown dwarfs, have been labeled planets by some astronomers.

A similar debris disk, called a circumstellar disk, developed around our own Sun shortly after its birth. From these disks, comets, asteroids and planets are made, and in at least one case even a habitable one, Earth. But don't expect to find any little green men on any potential planets around brown dwarfs.

"These would be very, very cold planets," said Charles J. Lada, an astrophysicist at the Smithsonian Astrophysical Observatory. "They're probably not really great places to have life."

In fact, the forecast could call for temperatures as low as minus 423 degrees Fahrenheit, he said. Everything would be frozen solid.

Brown dwarfs emit very little energy, and a world in orbit around one would afford days no brighter than twilight. Any potential life would have to play by biological rules we don't currently know of.

The discovery, funded by the National Science Foundation, was made in a region of space called the Trapezium cluster, where a thousand very young stars huddle together some 1,200 light-years away in the Orion Nebula.

Using a European Southern Observatory (ESO) telescope in Chile, Lada and his colleagues looked at 100 objects that had previously been suspected of being brown dwarfs. More than half (63 percent) emitted extra infrared light, indicating a ring of hot, glowing debris.

"The number of brown dwarfs that have disks is similar to the number of stars that have disks in Orion," Lada said in an interview.

After finishing their initial research, Lada and his colleagues also on a hunch searched through Hubble space telescope archives and found that other researchers had already spotted four of these disks in visible light but had not recognized them as circumstellar disks. These Hubble observations support the team's new conclusions.

Lada worked on the study with his sister Elizabeth A. Lada and August A. Muench, both of the University of Florida, and ESO astronomer Joao F. Alves, who cautioned that the presence of the dust disks does not guarantee existence of planets.

"It is entirely possible that the [Milky Way] Galaxy contains numerous planetary systems that orbit cold and dark, failed stars," said Alves. "Whether these disks can indeed form planetary systems, however, remains to be determined."

The findings do mean that lone planets drifting freely through space might be less common than thought.

Several dozen extrasolar planets, most of them many times more massive than Jupiter, have been discovered over the past six years. They all orbit stars. Over the same time frame, brown dwarfs, usually existing by themselves in interstellar space, have been found to be rather common.

Objects below 10 Jupiter masses might be planets, given the new findings. But Lada said any such planets probably would have formed in a conventional manner, around a star, to be later ejected into interstellar space by the gravitational tug of a passing star or some other means.

Such objects even could have been ejected by our Solar System, he said.

Further, the study found that in the Trapezium Cluster, which contains by far the largest number of known brown dwarfs, the bulk of those examined are of the larger variety. Proportionally, very few smallish brown dwarfs exist.

"This narrows the range of possibilities" for free-floating planets, Lada said, and will make the search "much more difficult, because if they are there they will be rare and difficult to detect," owing to their low mass and extremely low energy output.

Geoffrey Marcy, a renowned hunter of extrasolar planets from the University of California, Berkeley, was not involved in the research but called the evidence compelling. He is convinced that the excess infrared light from brown dwarfs measured in the study is in fact due to circumstellar disks.

Marcy said the new study does not change the view of extrasolar planets orbiting stars. All of them have masses of less than 13 Jupiters. Further study could find that some are slightly larger, he said.

"The bulk of the 67 extrasolar planets found so far have masses of less than three or four Jupiter masses," Marcy told SPACE.com.

Marcy, who with his colleagues has found more extrasolar planets than anyone, said detecting planets around a brown dwarf, even one that's a light year away, would be "an enormous challenge."