Telescope filter helps spot Earth-like alien worlds
In the hunt for planets around distant stars, the stars themselves are often the worst enemy. They're so bright that you rarely spot anything smaller than a gas giant, which isn't much help when you're trying to find habitable worlds. An alliance of American and Dutch researchers may have the ticket to locating Earth-like bodies, though. They've developed a new variety of coronagraph (a telescope filter that blocks starlight) powerful enough to give a much better view of the objects around stars, even when they're half as far from their hosts as Earth is to the Sun. The key is that it doesn't block light directly, like other coronagraphs -- it instead has the light waves cancel each other out, even in the infrared wavelengths where stars tend to blot out their orbiting companions.
The filter has only been in action with multiple telescopes for about a month, but the early results speak for themselves. In the picture you see above, the coronagraph helped make out Beta Centauri's multiple stars. The hope is that the technology will let astronomers detect more small planets through straightforward observation, rather than having to use indirect measurements that leave plenty of room for error. Don't be surprised if the rapidly expanding list of known exoplanets not only grows faster, but includes more examples that could support life.
[Image credit: Leiden University, University of Arizona]
