The Chandra X-ray Observatory has captured the first images of Mars taken at x-ray wavelengths. The Martian radiation is created in a process similar to the way light is created in fluorescent bulbs. X-rays from the Sun collide with oxygen atoms in the thin Martian atmosphere, about 75 miles (120 kilometers) above the surface. The solar photons excite an oxygen electron, bumping it up to a higher energy level. The excited electron quickly returns to its base energy level, emitting another x-ray in the process, which are what Chandra imaged. Fluorescent lights use ultraviolet radiation instead of x-rays. Images This remarkable Chandra image gave scientists their first look at X-rays from Mars. In the sparse upper atmosphere of Mars, about 120 (75 miles) kilometers above its surface, the observed X-rays are produced by fluorescent radiation from oxygen atoms. CREDIT: NASA/CXC/MPE/K.Dennerl et al. More Stories Mars to Get Closer than Ever in Recorded History in 2003 Where is Mars Now? Why a Mars Rock Hits Earth Every Month Ghosts of Impacts Past: Ancient Hidden Craters on Mars Revealed Solving the Mysteries of Mars Reveals More Chandra also detected x-ray emissions in a 4,350-mile (7,000-kilometer) ring around Mars. Researchers suspect that these photons are created in a similar way as solar x-rays excite electrons in oxygen and hydrogen atoms that have escaped Mars atmosphere.
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