Launch anticipated for groundbreaking X-ray lobster-eye mission

The Chinese Academy of Sciences (CAS) is set to launch its spacecraft, the Einstein Probe, in January 2024. This mission, in collaboration with the European Space Agency (ESA) and the Max Planck Institute for Extraterrestrial Physics (MPE), aims to survey the sky and detect powerful bursts of X-ray light emitted by mysterious celestial objects such as black holes and neutron stars. The spacecraft is equipped with innovative X-ray instruments that offer high sensitivity and a wide field of view, allowing for the discovery of new sources and the study of known celestial objects.

The Einstein Probe’s ability to monitor large areas of the sky at once makes it an invaluable tool for astronomical research. X-ray objects in the universe are highly variable, continuously brightening and dimming or disappearing for long periods. These objects, powered by cosmic events, emit X-ray light that provides fundamental information about enigmatic phenomena such as collisions between neutron stars, supernova explosions, and matter falling onto black holes. By monitoring these objects and studying their behavior over time, scientists can gain a deeper understanding of high-energy physics and the most energetic processes in the universe.

Moreover, the Einstein Probe’s capability to rapidly detect new X-ray sources is important for advancing our understanding of gravitational waves. Gravitational waves are created when massive objects like neutron stars or black holes collide, producing waves that travel through spacetime. Although detectors on Earth can register these signals, they often can’t pinpoint the exact source. However, when such cosmic collisions occur, they are accompanied by an enormous burst of energy across the light spectrum, particularly in X-rays. By promptly studying these short-lived events, the Einstein Probe can help identify the origins of gravitational wave impulses observed on Earth.

The spacecraft is equipped with two key instruments: the Wide-field X-ray Telescope (WXT) and the Follow-up X-ray Telescope (FXT). The WXT features an optical modular design inspired by a lobster’s eyes and innovative Micro Pore Optics technology. This allows it to observe nearly one-tenth of the celestial sphere in one shot, offering almost complete coverage of the night sky during its 96-minute orbits around Earth. When the WXT detects new X-ray sources or interesting events, the FXT, which is more sensitive, is used to study them in detail. To maximize the scientific potential of the Einstein Probe, ground-based and space-based telescopes operating at different wavelengths are also triggered to collect multi-wavelength data and enable comprehensive studies of these events.

ESA has played a significant role in the development of the Einstein Probe’s scientific instrumentation. It has provided support for testing and calibrating the X-ray detectors and optics of the WXT. ESA collaborated with MPE and Media Lario to develop the mirror assembly for one of the FXT telescopes. The mirror assembly for the other FXT telescope was contributed by MPE, which also developed the detector modules for both units. Additionally, ESA provided the electron diverter system to deflect unwanted electrons away from the detectors. Throughout the mission, ESA’s ground stations will be used to download data from the spacecraft.

The Einstein Probe mission represents a continuation of ESA’s commitment to advancing high-energy astronomy. Their previous missions, XMM-Newton and Integral, have significantly contributed to our understanding of X-rays and gamma-rays in the universe. ESA is also participating in the XRISM mission led by JAXA and NASA. Furthermore, the capabilities of the Einstein Probe complement in-depth studies conducted by other missions and pave the way for ESA’s NewAthena mission, which is currently being studied and is projected to be the largest X-ray observatory ever built.

To wrap it up, the upcoming launch of the Einstein Probe spacecraft marks an exciting collaboration between CAS, ESA, and MPE. With its advanced X-ray instruments and wide-field observation capabilities, this mission is poised to greatly expand our knowledge of celestial objects emitting X-ray light. By detecting new sources and monitoring known objects, the Einstein Probe will contribute to our understanding of high-energy physics, the origins of gravitational waves, and advancements in high-energy astronomy.