释义 |
DictionarySeex-ray astronomyEinstein Observatory
Einstein Observatory: see X-ray astronomyX-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X rays. ..... Click the link for more information. .Einstein Observatory NASA's second High-Energy Astrophysical Observatory, HEAO-2, launched in Nov. 1978 for X-ray observations and operated until loss of control gas in Apr. 1981. The (then) unique capabilities of its 60-cm grazing incidence telescope revolutionized X-ray astronomy, in the same way Uhuru had done a decade before. High-resolution maps were obtained of many extended sources (clusters of galaxies, supernova remnants), the first high-resolution spectroscopy was achieved on a few bright sources, and the enhanced sensitivity led to the discovery of several thousand faint sources (down to ˜10 nanojansky), mainly identified with normal galactic stars or active galaxies (quasars) at high redshifts. A catalog of Einstein Observatory sources is available as an extension to the EXOSAT Database. |