Einstein Probe Launches with a Mission to Monitor the X-ray Sky

Einstein Probe Launches with a Mission to Monitor the X-ray Sky

The Chinese Academy of Sciences spacecraft Einstein Probe lifted off on a Chang Zheng (Long March) 2C rocket from the Xichang Satellite Launch Centre in China at 15:03 CST / 07:03 GMT / 08:03 CET on 9 January 2024. With the successful launch, Einstein Probe began its mission to survey the sky and hunt for bursts of X-ray light from mysterious objects such as neutron stars and black holes.

Einstein Probe is a collaboration led by CAS with the European Space Agency and the Max Planck Institute for Extraterrestrial Physics, Germany.

To efficiently monitor the entire sky and routinely discover new X-ray sources, the Einstein Probe is equipped with two instruments that together deliver a wide and sensitive view of the celestial sphere: the Wide-field X-ray Telescope (WXT) and the Follow-up X-ray Telescope (FXT). The design of WXT’s optics is inspired by the eyes of lobsters; in a modular layout, it employs hundreds of thousands of square fibers that channel light onto the detectors. This gives Einstein Probe the unique capability to observe nearly one-tenth of the celestial sphere in a single glance. New X-ray sources spotted by WXT will be immediately targeted with FXT, which has a narrower view but is more sensitive and will capture more details.

ESA supported the testing and calibrating of the X-ray detectors and the optics of WXT and developed the mirror assembly of one of FXT’s two telescopes in collaboration with MPE and Media Lario. MPE contributed the mirror assembly for the other telescope of FXT, as well as the detector modules for both FXT units. ESA also provided the system to deflect unwanted electrons away from the detectors (the electron diverter). Throughout the mission, ESA’s ground stations will be used to help download the data from the spacecraft.

In return for these contributions, ESA will get access to 10% of the data generated by Einstein Probe’s observations.

The ability of the mission to spot new X-ray sources and monitor how they change over time is fundamental to improving our grasp of the most energetic processes in the Universe. Powerful blasts of X-rays occur when neutron stars collide, supernovas explode, and matter is swallowed by black holes or ejected from the crushing magnetic fields that envelop them.

“I would like to congratulate our colleagues at CAS on the successful launch of an innovative mission that is set to make great strides in the field of X-ray astronomy,” says Carole Mundell, ESA’s Director of Science. “At ESA, we value international collaboration to advance science and deepen our understanding of the cosmos. I wish the Einstein Probe team a very successful mission.”

“I am looking forward to the discoveries that Einstein Probe will enable,” says Erik Kuulkers, ESA’s Einstein Probe Project Scientist. “Thanks to its uniquely wide gaze, we will be able to catch the X-ray light from collisions between neutron stars and find out what is causing some of the gravitational waves we detect on Earth. Often, when these elusive space-time ripples are registered, we cannot locate where they are coming from. By promptly spotting the burst of X-rays, we will pinpoint the origin of many gravitational wave events.”

After launch, Einstein Probe reached its orbit at an altitude of approximately 600 km. The spacecraft circles the Earth every 96 minutes with an orbital inclination of 29 degrees and it is able to monitor almost the full night sky in just three orbits.

In the next six months, the operation team will be engaged in testing and calibrating the instruments. After this preparation phase, Einstein Probe will spend at least three years attentively watching the entire X-ray sky.

Click here to learn more about the Einstein Probe Mission.

Publisher: SatNow

GNSS Constellations - A list of all GNSS satellites by constellations


Satellite NameOrbit Date
BeiDou-3 G4Geostationary Orbit (GEO)17 May, 2023
BeiDou-3 G2Geostationary Orbit (GEO)09 Mar, 2020
Compass-IGSO7Inclined Geosynchronous Orbit (IGSO)09 Feb, 2020
BeiDou-3 M19Medium Earth Orbit (MEO)16 Dec, 2019
BeiDou-3 M20Medium Earth Orbit (MEO)16 Dec, 2019
BeiDou-3 M21Medium Earth Orbit (MEO)23 Nov, 2019
BeiDou-3 M22Medium Earth Orbit (MEO)23 Nov, 2019
BeiDou-3 I3Inclined Geosynchronous Orbit (IGSO)04 Nov, 2019
BeiDou-3 M23Medium Earth Orbit (MEO)22 Sep, 2019
BeiDou-3 M24Medium Earth Orbit (MEO)22 Sep, 2019


Satellite NameOrbit Date
GSAT0223MEO - Near-Circular05 Dec, 2021
GSAT0224MEO - Near-Circular05 Dec, 2021
GSAT0219MEO - Near-Circular25 Jul, 2018
GSAT0220MEO - Near-Circular25 Jul, 2018
GSAT0221MEO - Near-Circular25 Jul, 2018
GSAT0222MEO - Near-Circular25 Jul, 2018
GSAT0215MEO - Near-Circular12 Dec, 2017
GSAT0216MEO - Near-Circular12 Dec, 2017
GSAT0217MEO - Near-Circular12 Dec, 2017
GSAT0218MEO - Near-Circular12 Dec, 2017


Satellite NameOrbit Date
Kosmos 2569--07 Aug, 2023
Kosmos 2564--28 Nov, 2022
Kosmos 2559--10 Oct, 2022
Kosmos 2557--07 Jul, 2022
Kosmos 2547--25 Oct, 2020
Kosmos 2545--16 Mar, 2020
Kosmos 2544--11 Dec, 2019
Kosmos 2534--27 May, 2019
Kosmos 2529--03 Nov, 2018
Kosmos 2527--16 Jun, 2018


Satellite NameOrbit Date
Navstar 82Medium Earth Orbit19 Jan, 2023
Navstar 81Medium Earth Orbit17 Jun, 2021
Navstar 78Medium Earth Orbit22 Aug, 2019
Navstar 77Medium Earth Orbit23 Dec, 2018
Navstar 76Medium Earth Orbit05 Feb, 2016
Navstar 75Medium Earth Orbit31 Oct, 2015
Navstar 74Medium Earth Orbit15 Jul, 2015
Navstar 73Medium Earth Orbit25 Mar, 2015
Navstar 72Medium Earth Orbit29 Oct, 2014
Navstar 71Medium Earth Orbit02 Aug, 2014


Satellite NameOrbit Date
NVS-01Geostationary Orbit (GEO)29 May, 2023
IRNSS-1IInclined Geosynchronous Orbit (IGSO)12 Apr, 2018
IRNSS-1HSub Geosynchronous Transfer Orbit (Sub-GTO)31 Aug, 2017
IRNSS-1GGeostationary Orbit (GEO)28 Apr, 2016
IRNSS-1FGeostationary Orbit (GEO)10 Mar, 2016
IRNSS-1EGeosynchronous Orbit (IGSO)20 Jan, 2016
IRNSS-1DInclined Geosynchronous Orbit (IGSO)28 Mar, 2015
IRNSS-1CGeostationary Orbit (GEO)16 Oct, 2014
IRNSS-1BInclined Geosynchronous Orbit (IGSO)04 Apr, 2014
IRNSS-1AInclined Geosynchronous Orbit (IGSO)01 Jul, 2013