September 18, 2003

West Ford Dipoles

Today's Spacecraft of the Day is Project West Ford, which put into orbit the most and the smallest "spacecraft." The experimental system comprised hundreds of millions of small copper needles(dipoles) intended to reflect radio signals at 8 MHz, with transmitters at Westford, Massachusetts and Camp Parks in Pleasanton, California. The project was approved in 1961 and successfully launched on May 9, 1963, from the Western Test Range on an Atlas-Agena B, with a 19 kg payload of some 480 million 1.78 cm x 0.00178 cm AWG-53 copper needles. The primary payload was the MIDAS 6 MIssile Defense Alarm System, which remains in orbit (1963-014-A). An earlier MIDAS launch on October 21, 1961, failed to deploy the needles, and that spacecraft also remains in orbit today (1961-028-C).

Several early sources indicated that the dipoles had re-entered by 1966. However, it appears that many clumps of the needles are indeed still in orbit, adding to the orbital debris problem (pdf). For example, one clump is identified as 1963-014-E, and has the following orbit information, as of 11:21:28 AM UTC, Saturday, September 13, 2003:


    Eccentricity: 0.0046420
    Inclination: 87.3097°
    Perigee Height: 3,583 km
    Apogee Height: 3,676 km
    Right Ascension of Ascending Node: 263.1877°
    Argument of Perigee: 299.8841°
    Revolutions per Day: 8.67192725
    Mean Anomaly at Epoch: 59.7386°
    Orbit Number at Epoch: 27747

There are numerous clumps, which you can find by searching the database at heavens-above.com.

The project was quite controversial at the time, with astronomers and others concerned about the effects that the dipoles might have on astronomical observations and other telecommunications systems. Some details of this controversy are provided in this report (also linked in references below). Furthermore, one Tanya Levin presented a paper at a 1998 History of Science Society Meeting, entitled "Contaminating Space: Project West Ford and Scientific Communities, 1958-1965," which indicates that the controversy is not entirely over.

The West Ford Project was one of many novel experiments in the field of space communications, but it generated more than its share of debate among the scientific, engineering, and military communities.

References
M. P. Brown, Jr. (editor), Compendium of Communication and Broadcast Satellites: 1958 to 1980, IEEE Press, 1981, pp. 299-302

H. M. Jones, C. W. Perkins, and I. I. Shapiro, "Orbital lifetime of the West Ford dipoles," Science, 140, 1173,1963.

I. I. Shapiro, H. M. Jones, and C. W. Perkins, "Orbital properties of the West Ford dipole belt," Proc. IEEE, 52, 470-518, 1964.

D. C. MacLellan, W. E. Morrow, Jr., and I. I. Shapiro, "Effects of the West Ford belt on astronomical observations," Proc. IEEE, 52, 564-570, 1964.

I. I. Shapiro, "Last of the West Ford dipoles," Science, 154, 1445-1448, 1966.

D. R. Terrill, Jr., The Air Force Role in Developing International Outer Space Law, Air University Press, Maxwell Air Force Base, Alabama, 1999, Ch. 4 "Project West Ford"

West Ford is also mentioned in several NASA History documents: here, here, here, and here.

UPDATE: Going through some old papers I found this relevant reference:
Bruce R. Bowman, William N. Barker and William G. Schick, "Orbit Perturbation Analysis of West Ford Needles Clusters," AIAA 2000-4236. From the paper number, I think that this paper was presented at the 2000 AIAA Guidance, Navigation and Control Conference, August 14-17, 2000, in Denver, Colorado.

Posted by cdhall at September 18, 2003 01:02 PM | TrackBack (0)
Comments

You state West Ford was intended to reflect radio signals at 8 Mhz. This is not correct. The dipoles were intended to reflect 8 GHZ. This is a really big difference.

Posted by: James at October 5, 2004 10:29 AM
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