an exoplanet was discovered for the first time with an atmosphere that could be measured. The planet, GJ 1214b, is three times larger than earth and with a mass seven times greater. This study used near-infrared observations at the Very Large Telescope at Paranal Observatory in Chile. Although the planet has been shown to have an atmosphere, the chemical composition is still to be determined, with hydrogen, helium or water-steam all being possibilities.
Also in December a team of US and British scientists, using observations from NASA’s Spitzer Space Telescope, discovered exoplanet Wasp 12b. This Jupiter-sized gas planet has been found to contain a high proportion of carbon, suggesting that rocky exoplanets made of diamond or graphite could exist.
Several observations over the last two years have produced visual images of exoplanets. The first such image was obtained in 2008, of three exoplanets orbiting a bright star called HR 8799, lying some 129 light years from Earth and faintly visible to the naked eye. Recently further analysis on HR 8799 has shown up a fourth exoplanet (see picture). Together with the fact that there are two belts of debris orbiting the star—small rocky or icy objects, as well as large amounts of tiny dust particles – the existence of four giant planets makes HR 8799 similar to our own solar system though on a much larger scale.
Our solar system has four giant planets—Jupiter, Saturn, Uranus and Neptune, and our debris belts include the asteroid belt between the orbits of Mars and Jupiter and the Kuiper Belt, beyond the orbit of Neptune. Christian Marois, an NRC astronomer and lead author of the research which is published in Nature  said, “The images of this new inner planet are the culmination of 10 years’ worth of innovation, making steady progress to optimize every aspect of observation and analysis. This allows us to detect planets located ever closer to their stars and ever further from our own solar system.”
 Science, Vol. 330, 29 October 2010, p. 556.
 Nature, Vol. 468, 23 December 2010, pp. 1080–1083.