London, Jan 13 : A team of researchers have suggested that a direct view of planets in other solar systems could be possible using a balloon-borne telescope afloat in the stratosphere.

"It's one of those ideas that actually has a remote chance of making it off the drawing board," says team leader Wes Traub, a senior research scientist at NASA's Jet Propulsion Lab in Pasadena, California, US.

According to a report in New Scientist, if successful, the scheme would deliver images of extra solar planets which are impossible to see from the ground. This would all cost a fraction of what it would cost to do the job from space.

At latest count, astronomers have identified 270 exoplanets orbiting distant stars. Virtually all of these planets were detected by indirect means and are too faint and too close to the stars they orbit to be imaged directly.

Now, Traub and his collaborators say that at least some planets can be viewed just as easily, and far more cheaply, from the stratosphere.

Previous measurements have shown that light from distant stars remains relatively undisturbed while passing through the stratosphere, a region of the atmosphere stretching from 10 to 50 kilometers above the surface, where turbulence is low.

As part of the new research, astronomers have envisioned a telescope with a 1-to-2 metre mirror that would perform well enough to image approximately 20 exoplanets that lie relatively far away from the glare of their host stars.

The telescope would use a coronagraph, which blocks the light of a target star while allowing the light from surrounding planets to reach the camera. The camera would image through a variety of colour filters, which would provide clues to the atmospheric composition of any planets it sees.

The estimated cost of the project, dubbed "Planetscope", would be about 10 million dollars.

"It's the kind of thing that needs to be tried, because it's much cheaper than going to space," said Mike A'Hearn of the University of Maryland in College Park, US. (ANI)