The following list includes satellites and spacecraft tracked from the Zarya home location. Some of the frequencies are used, or have been used, by other satellites both now and in the past. However, the purpose of the Zarya list is to document only those signals actually tracked on active frequencies. The list evolves with time. Appearance on the list is not a guarantee that a particular satellite is currently operational or transmitting.
Some transmitters operate continuously and some are switched on and off periodically.