Free Republic

In the far future, we could reveal detailed views of distant worlds by turning our home star into a gravitational lens Diagram showing a conceptual imaging technique that uses the sun’s gravitational field to magnify light from exoplanets. This would allow for highly advanced reconstructions of what exoplanets look like. We now know of more than 5,000 exoplanets beyond the solar system. What we really understand about each of these worlds, though, is barely anything at all. Most of them have been seen only indirectly from their shadows as they cross in front of the stars they orbit. The...

Ten years ago, NASA researchers discovered that the Pioneer 10 and 11 spacecraft had fallen slightly behind course during their 35-year journeys to the outer reaches of the solar system. In what has become known as the Pioneer anomaly, which was the subject of one of the talks this weekend at the American Physical Society here in St. Louis, nobody knows for sure why it happened. It probably stemmed from leaking gas or heat. But there's also the possibility, however remote, that gravity doesn't behave the way we expect. Until recently, researchers haven't had the data to distinguish the different...