NRL-PL 151

Launch data:

Mission details:

• On Jan 29, 2020 at 2339 UTC two defunct satellites had a very near miss, probably less than 100 meters apart. The IRAS astronomical satellite, which operated from 1983 to 1985, and the NRO/NRL POPPY 5B signals intelligence satellite (codenamed GGSE 4?), which operated from 1967 to 1972, passed each other at a relative velocity of 14.7 km/s.