Despite serious problems with its main mirror, the Hubble Space Telescope observed X rays and infrared and ultraviolet radiation and discerned closely spaced features on distant objects. The Advanced X-Ray Astrophysics Facility was expected to be launched by NASA in 1998 and the Space Infrared Telescope Facility in 2000. Written records of eclipses of the moon and observations of the planet Venus date back to about 2000 BC in Babylonia. Early observatories consisted of relatively simple mechanical equipment used to measure the direction in which a celestial body was moving and its distance from the Earth. With the passing centuries, more sophisticated equipment, such as astrolabes, were invented.
Astrolabes are disks marked along the edges with degrees of the circle and with movable pointers.
They were used to determine the angular distance between points in the sky and to compare the positions of the planets or the moon to fixed stars. With the development of long-distance trade in the Mediterranean basin and later in China, navigation by the stars became a necessity. Accurate astronomical observations were of great use to agricultural communities in ancient Egypt. There the rising of Venus was used to plan the planting and harvesting periods. The development of astrology, in which the movement of the planets is believed to affect human life, also contributed to an interest in celestial objects.