BBC: As part of the European Union’s Galileo project, the European Space Agency launched the third and fourth satellites on a Russian Soyuz rocket over the weekend. The multibillion-dollar project is a European alternative to the US global positioning system. With four satellites, the system will be able to begin full-coverage testing for position tracking and ground-to-satellite system communications. The first of an additional 22 satellites is planned to be launched early next year, though the system will not begin operations until 2015. The full constellation of satellites, however, is not planned to be completed for a decade. The satellites themselves were built in a joint effort by Europe’s two primary space companies, Astrium and Thales Alenia Space. The Galileo system is designed to be more accurate than the current GPS network run by the US, though there are plans for upgrades to that system over the next decade as well.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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