* Astronomy

NASA will host a media teleconference on Thursday, April 30, at 2 p.m. EDT to discuss new data and findings revealed by the Mercury Surface, Space Environment, Geochemistry, and Ranging spacecraft known as MESSENGER.
The spacecraft is the first mission designed to orbit the planet closest to the sun. The probe flew past Mercury on Jan. 14, 2008, and Oct. 6, 2008, conducting the first up-close measurements of the planet since Mariner 10's final flyby on March 16, 1975.

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