What is Hubble's COSPAR ID?

Hubble’s COSPAR ID is 1990-037B.

This international designator identifies the spacecraft’s launch and its place in the launch sequence. “1990” is the launch year, “037” is the 37th launch cataloged that year, and “B” identifies Hubble as the second cataloged object associated with that launch. The launch was Space Shuttle mission STS-31, which deployed Hubble in April 1990.

A common mix-up is 1990-037A, which refers to another object from the same launch rather than Hubble itself. COSPAR IDs are distinct from satellite catalog numbers: the former encodes launch information, while the latter is a sequential tracking identifier used in systems such as the U.S. space-object catalog.

Hubble’s designation also helps distinguish it from later servicing missions and from the shuttle that carried it. Although Hubble has been repeatedly upgraded, its original launch identity remains unchanged.