Antenna

Volume 14, No. 2
April 2002

Mercurial Matters

SHOT 2002 in Toronto

Graduate Student Bonus

Survey of Local TV History

News of Mercurians and their Projects

Citizens (Band) of France Unite!

Printing a Revolution?

The End of Books

Reading Red Ochre: Parting Thoughts on Mixed Receptions

Dishing It Up: Really Big Antennas

Journal Announcements

Communications Under the Seas

Contact Us

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Dishing It Up: Really Big Antennas
Uplink-Downlink

The Dish (2000) introduced the moviegoers to the hidden world of spacecraft tracking, albeit at the Parkes telescope in the middle of Nowhere, Australia. Many other movies have incorporated dish antennas into their story lines, the most memorable to most is Carl Sagan’s Contact (1997). Despite the accurate (photographic) portrayal of what the antennas look like, they tell us nothing about their history—and that’s what Mercurians’ inquiring minds want to know!
The Deep Space Network (DSN) is the National Aeronautics & Space Administration’s (NASA) global system of spacecraft-tracking antennas. Created in 1958, the DSN grew up with NASA and the planetary missions managed by the Jet Propulsion Laboratory (JPL). The original DSN dishes were located in a desolate locale, a part of the Mojave Desert in southern California known as Goldstone, near (to stretch the meaning of “near”) the town of Barstow. Additional DSN dishes are located in Spain and Australia.
NASA has just published the first history of the DSN, Uplink-Downlink: A History of the Deep Space Network, 1957-1997 (Washington, D.C.: NASA SP-2001-4227, 2002). Its author, Douglas J. Mudgway, started working on the DSN at JPL in 1962, while it was still in its technological infancy. Not surprisingly, Uplink/Downlink focuses on the advanced technologies that made the DSN work over the past four decades. For example, it shows how DSN managers took advantage of the sweeping rise of digital technology in the 1980s and of specialized timekeeping devices such as atomic clocks and hydrogen masers.
Mudgway also highlights the role of the DSN in making significant scientific discoveries, especially in radio and radar astronomy. Additionally, he puts a human face on the DSN with his discussions of key leaders Eberhardt Rechtin and the late Nicholas Renzetti.


The Goldstone Complex

The Goldstone Dry Lake in the Mojave Desert is surrounded by hills which help protect the sensitive receivers from Earth-based radio “noise” that would interfere with weak signals from spacecraft. In 1958, Jet Propulsion Laboratory (JPL) team tested various sites for radio interference before selecting this spot. After less than a year of intense construction work, the site was ready to began operation to follow Pioneer 3 on its trajectory to the Moon. Now the Goldstone Deep Space Communications Complex fills 52 square miles with a whole community built up to operate the giant antennas and to develop prototype equipment to extend communication range and increase data transmission rates. Rather poetically, NASA named each of the antenna units for its first space mission or activity. Pioneer (DSS-11) was the original but was deactivated in 1981. The others are Echo (DSS-12), Mars (DSS-14), Uranus (DSS-15), Apollo (DSS-16), and Venus (DSS-13).

  Long Ago and Far Away

“Pioneer 10 Lives!” exalts the headline of a 2 March 2002 news update on the NASA website <Pioneer 10 News Update>. Larry Lasher, Pioneer Project Manager, reports enthusiastically that an uplink transmission from Goldstone, California, succeeded in reaching the famous 1972 spacecraft during its 30-year launch anniversary.
The signal went up from the Deep Space Network (DSN) 70 meter antenna DSS-14 (see below). The returning signal came in to DSN antenna DSS-63 in Madrid, Spain, 22 hours later. To the gratification of many, including those who worked on Pioneer 10 originally, this successful communication circuit indicates that the “spacecraft is still healthy” and is still generating power. Its thermometers reported in at the scales’ lowest ends—“extremely cold.” Remarkably, Pioneer 10 executed two commands and returned new data from the one scientific instrument still working, the Geiger Tube Telescope.

DSS-14 satellite dish
NASA built this huge dish antenna, Mars (DSS-14), in 1966 at 64 meters, then upgraded it to 70 meters in 1988 in preparation for Voyager 2’s 1989 visit to Neptune. Part of the Deep Space Network, its service has included tracking long-distance spacecraft. In early March 2002, it sent signals to Pioneer 10 (see above). The antenna also services radio and radar astronomy projects. Its narrow receiving beamwidth allows pointing accuracies of 0.006 degrees. So this is a precision device although the dish and the mounting structure on top of the pedestal weigh nearly 6 million pounds. The tiny dots below the antenna are trucks and cars. See <The Worldwide Deep Space Network>