NASA's Chandra X-ray Observatory went into Safe Mode on October 10. An investigation is underway to find the reason why. (Credit: NASA/CXC) NASA’s Chandra X-ray Observatory will soon be observing the cosmos once again, the space agency said Monday. A scare last week left the spacecraft in safe mode. Chandra is a space observatory that observes extreme objects that emit X-rays, like black holes. The problems with Chandra surfaced on October 10, just days after the iconic Hubble Space Telescope also went into safe mode due to issues with its gyroscopes, which help point the spacecraft. Together, the pair make up half of NASA's "Great Observatories" program.