The Max-Planck-Institut fuer extraterrestrische Physik (MPE), the Astrophysikalisches Institut Potsdam (AIP) and the Institute fuer Astronomie und Astrophysik der Universitat Tubingen (IAAT), together with European cooperation partners, have proposed to install an x-ray telescope on the International Space Station (ISS). The mission ROSITA will perform the first imaging all-sky survey in the medium energy x-ray range up to 10 keV with an unprecedented spectral and angular resolution. The main scientific goals are (1) to detect systematically all obscured accreting Black Holes in nearby galaxies and many new, distant active galactic nuclei, (2) to detect the hot intergalactic medium of several ten thousand galaxy clusters and groups and hot gas in filaments between clusters to map out the large scale structure in the Universe and to find in particular the rare massive distant clusters of galaxies for the study of cosmic structure evolution and (3) to study in detail the physics of galactic x-ray source populations, like pre-main sequence stars, supernova remnants, and x-ray binaries. In the hard x-ray band the ROSITA survey in this band, which was performed about 25 years ago. In the soft band the ROSITA survey will have a hundred times higher sensitivity and a hundred times better angular resolution than the last all-sky in this band, which was perforemd about 25 years ago. In the soft band the ROSITA survey will be more sensitive and have a substantially better energy and also angular resolution than the ROSAT all-sky survey. The telescope will consist of the seven 27-fold nested Wolter-1 mirror systems, the type already flown on ABRIXAS, and an ovel detector system currently being develoepd by MPE on the basis of the successful XMM pn-CCD technoloyg - a potential prototype for the planned ESA mission XEUS. Major improvements of the new camera are a higher time and energy resolution and significantly reduced ghost images. Within an industry study, recently completed, the general feasibility of such an astronomical survey telescope mounted on the ISS was established.