Though the Rossi telescope is no longer operational, NASA plans to launch a new X-ray telescope, the Neutron Star Interior Composition Explorer (NICER), in about two years. (sciencedaily.com)
Submitted as concepts for NASA's Explorer program, TESS and the $ 55 million Neutron Star Interior Composition Explorer (NICER) were chosen from four options as they «offer the best scientific value and most feasible development plans.» (seeker.com)
Previous simulations suggest that some of these rocky worlds may have interior compositions similar to Earth's. (sciencenews.org)