Rosetta flight director says Philae ready for release

When a European landing probe goes for a daring touchdown on a comet Wednesday, officials say it would help to have a little luck on their side.

Delta (δ) Cephei, prototype of Cepheids, which has given its name to all similar variable stars, was discovered 230 years ago by the English astronomer John Goodricke. The Cepheids role as distance calibrators for more than a century means δ Cephei is one of the most studied stars, but astronomers were shocked to discover that they lacked an essential piece of information…

In the final months of Europe’s LISA Pathfinder mission, scientists have found an unexpected use for the trailblazing testbed for a future gravitational wave observatory by tracking the tiny dings made by microscopic particles that strike the spacecraft in deep space, exploiting the impacts to learn about the population of dust grains cast off by comets and asteroids across the solar system.