http://www.smh.com.au/world/science/nasas-space-oddity-a-fluffy-foam-planet-20100105-lsdx.html WASHINGTON: The universe is looking more familiar and yet stranger at the same time.
This week at an astronomy meeting in Washington, the lead scientist for a new NASA space telescope announced the discovery of five more ''exoplanets'' far beyond our own solar system, and expressed optimism that his team is on a path to finding an Earth-sized planet in an Earth-like orbit in the near future.
But the new trove of data from the telescope, named Kepler, has also turned up space oddities that make astronomers wonder what exactly they're looking at.
For example, it found a star with a small orbiting object that is hotter than the star itself. It is too hot to be a planet but is the wrong size and density to fit any known profile for a dwarf star.
One of the five planets announced by William Borucki, the leading scientist for the telescope, is so fluffy that ''it has the density of Styrofoam'', he said.
Kepler was launched in March and is in an Earth-trailing orbit around the sun. It was designed to look at more than 100,000 stars in our galaxy in a patch of sky in the constellation Cygnus.
The telescope finds planets using a technique that measures the slight dimming of starlight as a planet passes in front of a star.
Most planets, in particular small, rocky bodies such as the Earth that orbit fairly far from the star, will not be properly aligned to be seen from our vantage point. But the detection of even a few ''Earths'' could be extrapolated to suggest that there are a great many such planets in our galaxy.
Although hundreds of exoplanets have been found since the first such detection in 1995, most are ''hot Jupiters,'' and none has been simultaneously the size of Earth and in the habitable zone - the orbit where water might be liquid at the surface.
Dr Borucki, in his address to the American Astronomical Society meeting, announced results from the first 43 days of Kepler data, with another eight months of data yet to be analysed.
The early results were necessarily skewed towards the easily detected planets, which tend to be large and orbit their parent stars in just a few days.
Dr Borucki said about 100 candidate planets were being studied as ground telescopes followed up the initial Kepler detections.
Other astronomers are enthusiastic about the news that has been announced by NASA.
''If there are Earth-like planets in habitable zones, we will find them,'' Mario Livio, an astrophysicist at the Space Telescope Science Institute in Baltimore, said. ''This is going to be really a treasure of data.''
Alan Boss, an astrophysicist at the Carnegie Institution of Washington, said Kepler was finding things that no one has seen before. ''They're going to find all kinds of weird stuff,'' he said. ''The universe, it really is a weird place. It's fantastic.''