The first link in a network of large dish antennae, designed specifically to track and receive signals from unpiloted spacecraft, became operational in California’s Mojave Desert. The network’s many accomplishments include relaying the first direct measurement of the astronomical unit; gathering data on the composition, mass, and other properties of the larger planets and their satellites; and measuring the effects of the solar wind and solar corona.
Humanity has always explored beyond Earth’s boundaries, but before the twentieth century, the only technology available to explore the night sky was the telescope. With World War II came huge advances in the infant science of rocketry, which enabled humans to explore space even further. In the post-World War II environment of the Cold War, both Soviet and Western blocs worked feverishly with captured German scientists and designs to create true space-going vehicles. The International Geophysical Year
The IGY’s first big achievement, the Soviet Union’s launch of the first Earth-orbiting artificial satellite, Sputnik 1, on October 4, 1957, shocked the United States into redoubling its efforts in its own space program. U.S. president Dwight D. Eisenhower implemented a new agency, the National Aeronautics and Space Administration
NASA, which became operational on October 1, 1958, inherited a number of existing projects and agencies. Among these agencies was the Jet Propulsion Laboratory
The first of these satellites, renamed Explorer 1
JPL director William H. Pickering already had his sights set on launching lunar probes as soon as possible. This plan dovetailed with the coming transfer of both JPL and the space program to NASA. The third and fourth Explorer launches were planned for late 1958 as Moon missions, with the hope of measuring cosmic radiation along the way as well as measuring the mass of the Moon. Knowledge from these probes would be a major American contribution to the IGY.
NASA Deep Space Network antenna dishes in Goldstone, California.
To receive the data being relayed back to Earth, a dedicated and vastly more powerful receiving device was needed. Deep space communication relies on microwave frequency bands. Because microwaves have low wattage and travel in straight lines, they need receivers that can remain precision-pointed at distant spacecraft. The devices that were nearest to these requirements at the time were the dish-shaped antennae used in radio astronomy. Furthermore, an array of receivers is also needed to convert a spacecraft’s incoming signals into graphic images, text, or numerical form, and to relay such information to those monitoring the flight.
Eberhardt Rechtin, head of JPL’s tracking and data acquisition office, envisioned a network of tracking antennae spaced around the world at intervals of 120 degrees (longitude), so that outgoing spacecraft would always be in direct communication with at least one of the stations. There would be no time, however, to build such a network before the late 1958 Moon launch date. Officials agreed to build one station only to make the deadline.
Rechtin appointed William D. Merrick, an electrical engineer who had previously worked on missile-tracking systems at White Sands, to build the antenna within one year. Merrick was known for “getting the job done” while maintaining high morale. Given a free hand to pick his team, he chose exceptional engineers from every department of JPL. Calling themselves the Hard Core Team, they worked tirelessly through the summer and fall of 1958 to design and build a 26-meter (85-foot) dish antenna at Goldstone Dry Lake
Goldstone was chosen for its isolation from urban areas, which have high concentrations of electromagnetic signals that crowd the sky. Located in a natural “bowl” landscape, which further shut out radio interference, the dish stands on Army-owned land about 30 miles from Barstow, California, the nearest town. The antenna itself is a parabolic dish that focuses radio waves on a tripod-shaped receiver that extends over the rim of the dish. Once completed in mid-October, 1958, tests were run, the new tracking station was pronounced operational on December 3, and the Deep Space Network (DSN) was born.
Three days later, Pioneer 3 was launched from its base in Florida. Unfortunately, the satellite did not accomplish its goal of reaching the Moon but plummeted back to Earth after a flight of about twenty-four hours. The Goldstone antenna, however, successfully tracked the entire flight and recorded its data. Three months later, Pioneer 4 was launched and traveled 435,000 miles into space, with the antenna receiving data until the craft’s batteries ran out. Although Pioneer 4, too, missed out on a lunar observation, the satellite did reveal a third radiation belt and became the first U.S. spacecraft to leave Earth’s orbit.
The Explorer program eventually ended, but numerous other U.S. space exploration missions followed. Having proven its value, the Goldstone antenna continued to track spacecraft for more than twenty years. A second, larger, antenna was built nearby in 1959, and the original was enlarged and enhanced over the years. Another antenna facility, similar to Goldstone, was completed in Woomera, South Australia, in 1960, and a third facility was constructed in South Africa in 1961. A third DSN antenna array is operating in Spain. Both the Spanish and the Australian stations have three working antennae, and Goldstone has six. The largest antenna is now 70 meters (230 feet) in diameter, a necessity for communication with the Voyager 1 and 2 spacecraft as they approach the far edge of known space.
The DSN has proven absolutely essential to continued exploration of the solar system by unpiloted spacecraft from Earth. Each flight requires the sending of commands, the updating of routine operating instructions, and the making of course changes and other adjustments. If a craft carries a lander, as have several missions to Mars, another entire group of instructions and manipulations have to be relayed upon the craft’s approach and landing.
From the spacecraft comes a steady stream of data back to Earth. This information, too, is received and translated by the network, and it is almost simultaneously sent to mission control. The DSN is an essential but largely unnoticed part of each venture into space. The network’s powerful antennae are always “catching” updated information about a craft’s location and trajectory. Through Mariner, Viking, Voyager, Galileo, and Cassini—an honor roll of exploratory projects—the network has provided a vital communication and research link.
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Leverington, David. A History of Astronomy from 1890 to the Present. New York: Springer-Verlag, 1995. A clearly written survey. The chapter on space research conveys problems, solutions, and the missions’ major discoveries. -
Mudgway, Douglas J. Big Dish: Building America’s Deep Space Connection to the Planets. Gainesville: University Press of Florida, 2005. An account of the land-based support stations for U.S. space missions. Provides some human interest background on the unsung “hero” engineers of these projects, as well as explanations of telemetry for nonspecialists. -
_______. Uplink-Downlink: A History of the NASA Deep Space Network, 1957-1997. Washington, D.C.: National Aeronautics and Space Administration, 2001. A comprehensive history of the network, arranged by spacecraft project names and eras. Summarizes mission results. Includes diagrams, photographs, and bibliographies.
United States Launches Vanguard Satellite Program
Soviet Union Launches the First Artificial Satellite
United States Launches Its First Orbiting Satellite
Pioneer Space Program Is Launched
Radio Astronomers Transmit Radar Signals to and from the Sun
NASA Launches Project Gemini
Ranger Program
Mariner 2 Becomes the First Spacecraft to Study Venus
Penzias and Wilson Discover Cosmic Microwave Background Radiation
Mariner Missions Conduct Mars Flybys
Surveyor Program Prepares NASA for Piloted Moon Landings
Bell Discovers Pulsars
Wheeler Refers to Collapsed Stars as “Black Holes”