Space telescope could be assembled by robot.

• Position: Observations

Seeing deep into space requires large telescopes. The larger the telescope, the more light it collects, and the sharper the image it provides. For instance, NASA's Kepler Space Observatory, with a mirror diameter of under one meter, is searching for exoplanets orbiting stars up to 3,000 light-years away. By contrast, the Hubble Space Telescope, with a 2.4-meter mirror, has studied stars more than 10,000,000,000 light-years away.

Now, researchers are proposing a space observatory that would have a primary mirror with a diameter of 100 meters. Space telescopes, which provide some of the clearest images of the universe, typically are limited in size due to the difficulty and expense of sending large items into space.

Sergio Pellegrino--professor of aeronautics and civil engineering at the California Institute of Technology, Pasadena, and senior research scientist at the Jet Propulsion Laboratory, La Canada Flintridge, Calif.--and colleagues would circumvent that issue by shipping the mirror up as separate components that would be assembled in space by robots.

Their design calls for the use of more than 300 deployable truss modules that could be unfolded to form a scaffolding upon which a commensurate number of...