National Aeronautics and Space Administration
NASA Space Science Data Coordinated Archive

About the Spacecraft Categories...

To improve the effectiveness of international distribution of satellite and space probe information via the SPACEWARN system, spacecraft are identified in categories according to the urgency and detail of information needed by the scientific community as follows:

Category 1:
Spacecraft that carry essentially continuous telemetry or radio beacons, usually on frequencies less than 150 MHz.
Category 2:
GPS constellation of positioning/navigational spacecraft.
Category 3:
GLONASS constellation of positioning/navigational spacecraft.
Category 4:
Occassionally, a list of bright, orbiting objects of visual magnitude 4 or brighter.

The SPACEWARN Bulletin contains the following information. Please note the accompanying explanations, where appropriate, as to coverage and sources of information since this is not repeated in the text.

A. List of Recent International Designations and Launch Dates (UTC). This list continues the tables given in previous bulletins.It also confirms the tentative designations assigned by the IUWDS World Warning Agency for Satellites acting on behalf of COSPAR via telegrams distributed over the SPACEWARN system.

B. Text of Launch Announcements. This section gives the texts of launching announcements of satellites and space probes received by the IUWDS World Warning Agency for Satellites at the NSSDC/WDC SI Greenbelt during the previous month.

C. Spacecraft Particularly Suited for International Participation. These data are based on launching announcements or on information received from individuals, launching authorities, and news magazines. Also included are decays of major objects, and miscellanous items.

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