On April 24, 1990, the Space Shuttle Discovery was launched in its STS-31 mission. In its cargo bay, it carried a really special payload, the Hubble Space Telescope. The day after it was deployed in its orbit, just over 550 km (about 342 miles) altitude. On June 25, Hubble sent its first images, which revealed a flaw in its primary mirror that reduced its usefulness. The first of a series of service missions turned what had threatened to turn into a terrible failure into a symbol for science and technology that goes far beyond astronomy.