Orbiting Solar Observatory

History

Nancy Roman oversaw the development of the Orbiting Solar Observatory program from 1961 to 1963.

The basic design of the entire series featured a rotating section, the "Wheel", to provide gyroscopic stability. A second section, the "Sail", was driven electrically against the Wheel's rotation, and stabilized to point at the Sun. The Sail carried pointed solar instruments, and also the array of solar photovoltaic cells which powered the spacecraft. The critical bearing between the Wheel and the Sail was a major feature of the design, as it had to operate smoothly for months in the hard vacuum of space without normal lubrication. It also carried both the power from the Sail and the data from the pointed solar instruments to the Wheel, where most of the spacecraft functions were located. Additional science instruments could also be located in the Wheel, generally looking out on a rotating radius vector which scanned the sky, and also across the Sun, every few seconds.

OSO 1 (OSO A) was launched on March 7, 1962.

OSO B suffered an incident during integration and checkout activities on April 14, 1964. The satellite was inside the Spin Test Facility at Cape Canaveral attached to the third stage of its Delta C booster when a technician accidentally ignited the booster through static electricity. The third-stage motor activated, launched itself and the satellite into the roof, and ricocheted into a corner of the facility until burning out. Three technicians were burned to death. The satellite, although damaged, was able to be repaired using a combination of prototype parts, spare flight parts and new components. It was launched ten months later on February 3, 1965 and was designated OSO 2 (OSO B2) on orbit.

OSO C never made it to orbit. Liftoff took place on August 25, 1965 and all went well through the second stage burn. During the coasting phase prior to third stage separation, its rocket motor ignited prematurely. This registered on ground readouts as an attitude disturbance followed by loss of second stage telemetry, and although the third stage managed to separate itself, it suffered from an 18% drop in thrust. The OSO spacecraft could not attain orbital velocity and instead fell back into the atmosphere and burned up. The failure was suspected to have been caused by a modification to the igniter mechanism in the third stage after some minor technical difficulties experienced on the previous Delta C launch (TIROS 10 on July 2).

OSO 3 (OSO E1) was launched on March 8, 1967.

List of OSO telescopes

Further developments

Another satellite using the Orbiting Solar Observatory platform was developed and launched: the Solwind satellite. It was launched February 24, 1979. It was operated by the DoD Space Test Program. It was destroyed September 13, 1985 on an ASAT missile test.

References

References

1. Todd Neff (2010) [http://www.earthviewmedia.com/books/jars.html From Jars to the Stars: How Ball Came to Build a Comet-Hunting Machine] {{Webarchive. link. (18 March 2018 Denver, CO.: Earthview Media.)
2. "Roman, Nancy Grace." in ''American Men & Women of Science: A Biographical Directory of Today's Leaders in Physical, Biological, and Related Sciences''. Ed. Andrea Kovacs Henderson. 30th ed. Vol. 6. Detroit: Gale, 2012. 339. Gale Virtual Reference Library.
3. "OSO 1, 2, C, 3, 4, 5, 6".
4. (April 1966). "History of Orbiting Solar Observatory, OSO-2". NASA{{}}Goddard Space Flight Center.
5. (October 1966). "Delta Vehicle Flight Failure Report, Launch 33". NASA{{}}Goddard Space Flight Center.
6. "Trajectory Details OSO 1".
7. "Trajectory Details OSO 2".
8. "Trajectory Details OSO 3".
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10. (3 March 1967). "WATCH TO BE KEPT ON SUN". [[The Canberra Times]].
11. "Trajectory Details OSO 4".
12. "Trajectory Details OSO 5".
13. "The Fifth Orbiting Solar Observatory". NASA.
14. (24 January 1969). "Safeguard for spacemen". [[The Canberra Times]].
15. "Trajectory Details OSO 6".
16. "The Sixth Orbiting Solar Observatory". NASA.
17. "Trajectory Details OSO 7".
18. "The Seventh Orbiting Solar Observatory". NASA.
19. (2 October 1972). "IN BRIEF". [[The Canberra Times]].
20. "Trajectory Details OSO 8".
21. "The Eighth Orbiting Solar Observatory". NASA.
22. "Advanced OSO". NASA.