Chinese researchers are preparing to launch a new X-ray astronomical satellite, Einstein Probe (EP), by the end of this year. The principal investigator of the satellite project, Yuan Weimin, who is also a researcher at the National Astronomical Observatories of the Chinese Academy of Sciences, announced the latest progress on the EP project at the recent 35th National Symposium on Space Exploration. According to Yuan, the probe has entered the final stage of development and is expected to capture the first light from supernova explosions, search for and pinpoint gravitational wave sources, and observe the mysterious transient phenomena in the universe.
The project aims to detect transient and explosive sources in the universe, many of which radiate huge amounts of energy in a short period and show complex brightness variations in the X-ray band. These fast transient sources are crucial to cosmology and galaxy studies but are currently poorly understood by scientists, Yuan explained. He also highlighted the need for a new generation of detection equipment with extremely large fields of view, high sensitivity, high resolution, and fast response capabilities.
To develop such equipment, Chinese scientists turned to the lobster’s eye, which is different from other animals. Lobster eyes consist of numerous tiny square tubes that point to the same spherical center, allowing light from all directions to reflect in the tubes and converge on the retina, giving the lobster a large field of view. Scientists then simulated the lobster eye to create a telescope to detect X-rays in space.
Through cooperation with other organizations, the X-ray Imaging Laboratory of NAOC began research and development work on lobster-eye X-ray imaging technology in 2010 and finally made a breakthrough. The team carried out test validation of the technology on the telescope Lobster Eye Imager for Astronomy (LEIA) — a pathfinder of the EP instrument — which was launched in July 2022, and revealed the world’s first batch of large-field X-ray snapshots of the sky captured by the LEIA.