Chandra X-Ray Observatory

The Chandra X-Ray has been NASA's flagship mission for X-Ray astronomy. It was first launched in July 23, 1999 and it is telescope that is designed to detect hot regions of the universe, such as exploding stars, clusters of galaxies, and matter around black holes. Since X-rays are absorbed by the Earth's atmosphere, Chandra must orbit above it. The observatory moves by the use of thrusters, one for propulsion and another for momentum unloading. The path it takes around the Earth is an elliptical orbit, in which the thrusters apply torques to help it maintain its altitude. The power of the observatory comes from the Sun's rays, which is then stored in its batteries and distributed throughout its system. Chandra's altitude is 200 times the height of Hubble, almost a third of the way to the moon. Chandra is also the largest space craft launched at a length of 45 feet and the mission that deployed it was commanded by the first woman commander. Chandra has the ability to detect particles entering a black hole up to the last second! This is why when it comes to quasars or supermassive black holes at the center of galaxies, or any other phenomena with the production of high energy light, Chandra is the telescope to use.
Its telescope consists of different lenses than usual optical telescopes. Since the photons its observing  are at a higher energy, they ricochet off the mirrors if they are at a grazing angle. Thus, they have to be parallel to the incoming X-rays, which is why they are barrel shaped, rather than disk shaped. Another interesting feature is that the smoothness of the mirrors have been reached to a few atoms. This is the equivalent of making the Earth's surface so smooth that Everest would be less than two meters tall. They are coated with the reflective and rare metal Iridium.

Coating the mirrors at Optical Coating Laboratories inc.
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