At long last, two teams of scientists have directly glimpsed the feeble light of planets orbiting distant stars through the lenses of telescopes. Before now, all of the 325 planets discovered outside our solar system had been located by indirect means, such as measuring their gravitational effects on their host star.
The two teams used enhanced optical techniques to bring the planets into view. One group, led by Paul Kalas of the University of California-Berkeley, used the Hubble Space Telescope to block the blinding light of the star Fomalhaut to resolve a planet orbiting in the star's surrounding disk of dust. The other group, a Canadian team led by Christian Marois of the Herzberg Institute of Astrophysics in British Columbia, saw not one but three planets around the star HR 8799. They used a method called adaptive optics to sharpen an Earth-based telescope image enough to spot the planetary system. Now, scientists can scan the light from these planets to learn what they are made of, their temperatures, and other intriguing details.