NICER

NICER (for Neutron Star Interior Composition Explorer) is an X-ray telescope deployed in 2017 on the International Space Station (ISS) to observe X-rays from neutron stars. Its one scientific instrument is XTI ("X-ray timing instrument"). XTI consists of fifty six X-ray sensors that are sensitive (through grazing incidence optics) to a small portion of the sky. It does not image, i.e., it is intended to view a point source, but the sensors record photon energy (spectroscopy information) and precise time of reception. The goal is to record the X-ray light curve of pulses from X-ray pulsars.