This is a fabulous technical advancement for science

Anne Kinney Nasa

On Monday night, the two 10-metre (33-foot) Keck telescopes on Mauna Kea in Hawaii produced a combined image of HD61294, a faint star in the constellation Lynx.

The two telescopes form what is known as the Keck Interferometer.

"Successfully combining the light from the two largest telescopes on Earth is a fabulous technical advancement for science," Nasa Astronomical Search for Origins Program Director Anne Kinney said.

"This will open the possibility of obtaining images with much greater clarity than ever before," she said.

To capture starlight from HD61294, both Keck telescopes fed light into a beam combiner and camera. Adaptive optical systems on both telescopes removed the distortion caused by the Earth's atmosphere.

Planet hunt

Nasa will continue testing the pair for several months before inviting proposals to use the system.

Scientific operations are due to begin in the autumn

One plan is to continue the search for planets outside our own Solar System. Since 1995, astronomers have discovered more than 50 planets orbiting other stars. However, with current technology, scientists can only find very large Jupiter-like planets located close to their parent suns.

The Keck Interferometer will be able to detect planets farther from their parent stars - planets which are more likely to harbour life.

The successful link-up means that the Nasa interferometer has gone into operation ahead of a similar European project - the Very Large Telescope (VLT) project at the European Southern Observatory in Chile.

The VLT interferometer's main components are four 8.5-metre (28-foot) telescopes, three of which are now in operation.