The month of December this year marks the fifth anniversary of the launch of ESA’s Gaia spacecraft. The mission, now operating continuously near the Earth-Sun L2 Lagrangian point, has already revolutionized many fields of astronomy, thanks to the broad and exquisite quality of the data it is producing.

For the first time since 2012 the year that just ended did not break all records of annual NEO discoveries. This was mostly due to unusually poor weather in Hawaii, where many current NEO discovery surveys are located.

On 22 June 2019, around 21:26 UT (17:26 local time), a roughly 5-metre object entered the atmosphere over the Caribbean Sea, and exploded at an altitude of about 25 km over the sea surface, releasing an energy roughly equivalent to 3 kt of TNT. The explosion was first detected by the Geostationary Lightning Mapper (GLM) instrument on board the GOES-16 geostationary satellite.

On 19 October a very small asteroid, designated as 2018 UA, was discovered by the Catalina Sky Survey, and quickly flagged as a potential very close approacher. Immediate follow-up observations by both Catalina and the Spacewatch project led to a much more accurate orbit solution.

The number of known NEAs reached the round total of 20 000 at the end oflast month. This group of asteroids is steadily growing at a pace of roughly 160 new discoveries each month, thanks to the work done by the main asteroid surveys.

March 2020 Newsletter