You are witnessing an historial moment: This is the first image ever obtained from Mercury's orbit. It was taken by NASA's Messenger, the first human-made spaceship to orbit this battered scorching hell.
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The photograph—which was taken yesterday, March 29, 2011 at 5:20am EDT—shows the surface of the innermost planet of the Solar System with unprecedented detail. Messenger—MErcury Surface, Space ENvironment, GEochemistry and Ranging—will now begin to map and study the planet in detail, following the work of Mariner 10. Mariner was the first space probe to obtain images of Mercury while flying by it in 1975. Messenger, however, will orbit the planet acquiring tons of information about its composition, geological history and magnetic field.
Messenger is also designed to investigate some of Mercury's strangest features. First, she will help scientists to discover what is the nature of the radar reflecting material on both its poles—which have permanently shadowed craters that contain ice all year around in a planet that has a 700 K temperatures (426ºC/800ºF) on its hottest point. She will also study its liquid core, which has the highest concentration of iron in our home star system and makes the planet have its own magnetic field, just like planet Earth.
But even more importantly, Messenger will study one of the most shocking discoveries in the history of astronomy: The large amounts of water found on its exosphere, which was first detected on the spaceship's July fly-by. As NASA's Thomas Zurbuchen said back then: "Nobody expected that. I don't know a single person that did. We were astonished, just astonished."
NASA's Messenger is a very unique spacecraft. Being so close to the Sun, she counts with a unique shield that protects her instruments from the fiery temperatures. The ship is made of graphite fiber and cyanate ester, a material that has long-term thermal stability. Inside, a computer with two radiation-resistant IBM RAD6000 processors controls the spaceship instruments and avionics. The main processor, which runs at 25MHz vs the 10MHz of the backup processor, is responsible of gathering all the data, compressing it and sending it to Earth using her three antennas. Everything is powered by two solar panels that provide with 450 watts while in orbit.
NASA will publish more images and details of the first findings later today, so come back later for more.