China launches X-ray satellite Einstein Probe for violent cosmic phenomena observation

China successfully launched a new X-ray satellite into its planned orbit from the Xichang Satellite Launch Center in southwest China on Tuesday.

The carrier rocket, coded Long March-2C, blasted off at 3:03 p.m. (Beijing Time), carrying the Einstein Probe, which is tasked with observing distant flashes from cosmic events.

The launch marks the 506th mission for the Long March series of carrier rockets.

The Einstein Probe, which has a designed life of five years, adopts the astronomical time-domain observation method to carry out high-sensitivity real-time dynamic sky survey monitoring in the soft X-ray band. It systematically discovers high-energy transient and abrupt objects in the universe, monitors the activity of known objects, and explores their nature and physical processes.

The satellite carries two payloads: a Wide-field X-ray Telescope (WXT) and a Follow-up X-ray Telescope. Scientists mimicked the special structure of the lobster eye in developing WXT, which can simultaneously achieve wide-field observation and X-ray-focused imaging.

"The Einstein Probe can capture sudden cosmic burst events or violent activities of celestial bodies. This kind of celestial body that suddenly appears in the universe, lasts for a few moments, and then disappears quickly is called a transient," Yuan Weimin, chief scientist of the Einstein Probe, told China Media Group (CMG).

According to the scientist, there are many spectacular transients and bursts in the universe, from stellar activities near the solar system to gamma-ray bursts from the distant early universe, and they can generate huge radioactive energy in a very short period of time, which are concentrated in the X-ray band, producing complicated and changing brightness just like those sparkling fireworks.

Such transients and bursts originate from the critical stages of the formation and evolution of celestial bodies and carry key information for the study of the universe. However, absorbed by the Earth's atmosphere, these X-rays that contain valuable information cannot reach the ground, according to Yuan.

He said that these transients are relatively far away with signals that are relatively dim, and they appear randomly in space.

"We don't know when and in what direction they appear. So it is difficult for current satellites to detect them, and we need a monitor with very high sensitivity and large field of view," the scientist told CMG.

"That's why we developed the Einstein Probe to capture these more remote and dimmer transients and bursts," he said.