The Apollo Telescope Mount, or ATM, was a crewed solar observatory that was a part of Skylab, the first American space station. It could observe the Sun in wavelengths ranging from soft X-rays, ultra-violet, and visible light. The ATM was designed and construction was managed at NASA's Marshall Space Flight Center. It included eight major observational instruments, along with several lesser experiments. The ATM made observations at a variety of wavelengths, including X-Rays, Ultraviolet, and Visible light.