STEVE INSKEEP, host:
Here's some news that really is news, even if you think that you've heard it before. Astronomers say they have snapped actual pictures of planets orbiting distant stars. Astronomers have made similar claims from time to time over the past 15 years, but this time they say, it's real. NPR's Richard Harris reports.
RICHARD HARRIS: Astronomers have detected more than 300 planets around distant stars. Typically they find wobbly stars and infer that the wobble is caused by the gravitational tug of a nearby planet. But pictures of a planet, well, that's another story. Now, Science magazine has published images that make that claim. Paul Kalas at the University of California at Berkeley tells his story of discovery. It begins with a star called Fomalhaut. It's a mere 25 light years away from us and shrouded in a giant cloud of dust.
Mr. PAUL KALAS (University of California, Berkeley): The original goal since 1993 was to find the dust cloud, to image it, to study how big it is, what its colors were, did it have blobs or warps?
HARRIS: Blobs and warps can be caused by a big object like a planet nearby, and sure enough, Kalas found not only blobs and warps but something that he says is indeed a planet. It's probably about the size of Neptune or Jupiter and herding the dust cloud around the star like a sheep dog. And now they've published a photograph, but before you rush out to look at our website, you should know that the spot on the photograph is apparently not the planet itself. Astronomers say it looks way too bright for that. But Kalas has an explanation.
Mr. KALAS: We have to speculate that there is a massive ring system, a massive disc of dust around the planet itself, something similar to Saturn's rings but much larger, and that system of rings is reflecting light back toward us.
HARRIS: Other features of this putative planet are also quite surprising to astronomers.
Mr. MARK KUSHNER (Goddard Space Flight Center, Maryland): It's almost like they went fishing in a fishbowl, and they pulled out a whale.
HARRIS: Mark Kushner is at NASA's Goddard Space Flight Center in Maryland.
Mr. KUSHNER: It's a very massive planet located far from the star where massive planets maybe shouldn't be.
HARRIS: On the other hand, he says, it really does look like the image they have reveals a planet. So it's likely that astronomers are just discovering that planets can form in places and in ways that they hadn't previously suspected. The second discovery, also in Science, reveals not just one but three massive planets around a different star. They are also in far-out orbits and they are also huge gas giants, even bigger than Jupiter. Ray Jayawardhana is an astronomer at the University of Toronto.
Mr. RAY JAYAWARDHANA (Astronomer, University of Toronto): It's pretty cool to seeing a three-planet system image.
HARRIS: Jayawardhana isn't involved in the latest studies, but in September, he published an image of yet another putative planet. So far, he hasn't convinced his colleagues that his is also a planet, but he is gathering more evidence to make the case. He is thrilled to be part of what seems to be a new era of astronomy.
Mr. JAYAWARDHANA: I think the fact that you have three discoveries announced within two months of each other is telling you the time is right.
HARRIS: What are the prospects of seeing an Earth-like planet around a sun-like star?
Mr. JAYAWARDHANA: That's a little ways away, I'm afraid.
HARRIS: But not at all impossible. The next generation space telescope that will replace the Hubble in the coming decade could well send us back a picture of one of those distant worlds. Richard Harris, NPR News.
INSKEEP: This is NPR News.