DSN antenna. Photo: NASA/JPL

Preparing for the communication needs of an expected population boom in interplanetary spacecraft, NASA has selected a builder to add an advanced dish antenna, 34 meters in diameter (112 feet), near Madrid, Spain, one of the three sites of the agency's Deep Space Network.

The Deep Space Network is a global system for communicating with interplanetary spacecraft.

"We are getting ready for a crunch period beginning in November 2003," said Rich Miller, head of planning and commitments for the part of NASA's Jet Propulsion Laboratory in Pasadena, Calif., that manages the network. In late 2003 and early 2004, the United States, Europe and Japan will each have missions arriving at Mars, two other spacecraft will be encountering comets, and a third comet mission will launch. Several other missions will have continuing communication needs.

NASA has selected Schwartz-Hautmont Construcciones Metalicas S.A. of Tarragona, Spain, as the successful bidder to build a new antenna to be completed at the Madrid complex by November 2003. The antenna is the biggest piece in about $54 million worth of improvements that NASA's Office of Space Science, Office of Space Flight, and Space Operations Management Office have set as priorities for increasing the Deep Space Network's capabilities by late 2003. Other parts of the plan would improve the capabilities of existing antennas at all three of the network's tracking complexes: Madrid; Canberra, Australia; and Goldstone, near Barstow, Calif.

The Deep Space Network communicates with spacecraft that are anywhere from near Earth to out past Pluto. The network uses clusters of antennas at the three sites spaced approximately one-third of the way around the Earth from each other so they can cover spacecraft in any direction as the world turns. Each station has one 70-meter diameter (230-foot) antenna, plus several smaller ones.

Projections for demands on the network during the November 2003 to February 2004 period indicate the greatest need for increased communications capacity will be at Madrid. NASA plans to land two rovers on Mars in early 2004. Building a new 34-meter, antenna in Madrid would add about 70 hours of spacecraft-tracking time per week during the periods when Mars is in view of Madrid. The Madrid complex's current capacity is 210 hours within Mars view periods per week.

JPL, a division of the California Institute of Technology in Pasadena, manages the network for NASA.