Abstract
The upcoming launches of the major X-ray space observatories XMM and Astro E will provide some of the first high sensitivity, high resolution X-ray spectra of a wide range of astrophysical sources. The two missions are actually quite complementary in their attributes. XMM, which is an ESA mission planned for launch in December 1999, will carry a high throughput reflection grating spectrometer optimized for the energy band 0.3-2 keV, while the Japanese/US mission, Astro E, planned for launch in January 2000, will carry a nondispersive microcalorimeter experiment optimized in the energy band 1-10 keV. In addition, both missions will carry large area imaging CCD experiments for spectroscopy of very faint sources with more modest spectral resolution. I will review the essential characteristics of these missions, and will provide some examples of the types of astrophysical investigations which are planned.