Satellite watching

Amateur satellite spotting traces back to the days of early artificial satellites when the Smithsonian Astrophysical Observatory launched the Operation Moonwatch program in 1956 to enlist amateur astronomers in an early citizen science effort to track Soviet sputniks.

American officials were reluctant to provide information about the satellite, and instead, Ted Molczan, as the article says, "uncovers some of the deepest of the government’s expensive secrets and shares them on the Internet.

[8] During the 64th International Astronautical Congress 2013 in Beijing a citizen science method to track satellite beacon signals by a Distributed Ground Station Network (DGSN) was presented.

[9][10] The purpose of this network at announcement was to support small satellites and cubesats projects of universities.

[needs update] In 2019, amateur sky-watchers analyzed the high-resolution photograph of an Iranian launch site accident tweeted by US President Trump and identified the specific classified spysat (USA-224, a KH-11 satellite with an objective mirror as large as the Hubble Space Telescope) that had taken the photograph, and when it was taken.

[11] As with any sky-watching pastime, the darker the sky the better, so hobbyists will meet with better success further away from light-polluted urban areas.

[15] They can be distinguished from aircraft because satellites do not leave contrails and do not have red and green navigation lights.