Current & Future Missions
MESSENGER successfully flew by Mercury on September 29, 2009, gaining a critical gravity assist that will enable it to enter orbit about Mercury in 2011.
This mission to Mercury has been given full approval as an ESA cornerstone mission. The mission as now envisioned will consist of two modules. The Mercury Planetary Orbiter (MPO) will perform global remote sensing and radio science investigations. The Mercury Magnetospheric Orbiter (MMO) will carry the field, wave, and particle instruments in an eccentric orbit around Mercury.
Sunrise on Mercury
Sunrise and sunset on Mercury are spectacles to behold. Two and one half times larger in the sky than seen on Earth, the sun appears to rise and set twice during a Mercurian day. It rises, then arcs across the sky, stops, moves back toward the rising horizon, stops again, and finally restarts its journey toward the setting horizon. These aerial maneuvers occur because Mercury rotates three times for every two orbits around the sun and because Mercury's orbit is very elliptical.
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