This paper reviews the important progress made in the field of astronomy in 2021, including a series of significant achievements and events, as listed below:probes from various countries arrived on Mars and carried out scientific research; the Insight revealed the interior structure of Mars for the first time; LHAASO observed photons of 1.4 PeV; DAMPE obtained precise energy spectrum covering the energy range 70 GeV to 80 TeV of helium nucleus; IceCube captured neutrino from a tidal disruption event and a particle shower at the Glashow resonance. Astronomers also found the evidence of dark energy existence in the early time of the Universe, released the latest research results of the chang'e-5 samples, found an astronomical optical observing site in Lenghu, which was the best in China, detected the gravitational wave definitely from the neutron-black hole coalescence for the first time, discovered the observational evidence showing some fast radio bursts originated from a magnetar, studied a fast radio burst comprehensively with the help of FAST telescope, proposed a novel method to obtain the mass of a black hole, published the polarized image of black hole M87^*. In addition, James Webb Space Telescope was launched, and Chinese Xihe solar satellite was successfully launched as well.

Mars  /  cosmic ray  /  Chang'e-5  /  fast radio burst  /  neutrino