RHYOLITE / AQUACADE
In the 1963-1965 time frame, the CIA designed a new type of SIGINT (Signal Intelligence) satellite system under project RAINFALL. The main purpose of the system was intercepting telemetry signals (Telemetry Intelligence, TELINT; a.k.a. Foreign Instrumentation Signals Intelligence, FISINT), primarily of Soviet strategic missile tests from the Tyuratam and Sary Shagan test centers. The NSA also got involved by 1965, and in 1966, a contract to build four satellites was awarded to TRW. The unclassified numerical designation was Program 720 and the satellites were code-named RHYOLITE. The NRO was the overall managing organization for the program.
RHYOLITE has not been declassified so far, and therefore no confirmed details about the satellites are available. Total mass is estimated to be around 700 kg (1500 lb), and the main antenna dish probably had a diameter of around 20 m (65 ft). The first RHYOLITE was launched into a geostationary orbit by an Atlas-Agena D in June 1970, followed by a second one in March 1973. In 1975, RHYOLITE was renamed to AQUACADE and renumbered Program 472, after the original name had been compromised.
The RHYOLITE/AQUACADE program was also known as Mission 7600, and the individual satellites therefore received Mission designators 7601 and up. Each one was active for around 10 years, and they were eventually succeeded in Mission 7600 by the much bigger ORION series.
RHYOLITE/AQUACADE Launch List
- No.: Sequential flight number for the RHYOLITE/AQUACADE program
- Name: Unclassified name of the satellite. The OPS number ("OPS" standing for "Operations") is a random number given to all military-related satellite launches between 1963 and May 1984 (when "OPS" was replaced by a sequential "USA" number).
- Mission: Each RHYOLITE/AQUACADE mission had a unique NRO Mission number in the 76xx range.
- COSPAR ID: International designation of the satellite
| No. | Name | Mission | COSPAR ID | Launch | Launch Vehicle |
|---|---|---|---|---|---|
| 1 | OPS 5346 | 7601 | 1970-046A | 19 Jun 1970 | SLV-3A Atlas-Agena D |
| 2 | OPS 6063 | 7602 | 1973-013A | 6 Mar 1973 | SLV-3A Atlas-Agena D |
| 3 | OPS 4258 | 7603 | 1977-114A | 11 Dec 1977 | SLV-3A Atlas-Agena D |
| 4 | OPS 8790 | 7604 | 1978-038A | 7 Apr 1978 | SLV-3A Atlas-Agena D |
RHYOLITE/AQUACADE launches
Main Sources
[1] Desmond Ball, Bill Robinson and Richard Tanter:
The SIGINT Satellites of Pine Gap:
Conception, Development and in Orbit, Nautilus Institute for Security and Sustainability, October 2015
[2] Gunter Krebs: Gunter's Space Page (for launch lists)
Back to Directory of U.S. Military Rockets and Missiles, Appendix 3
Last Updated: 30 June 2025