Deep Space Network Gears Up For Interplanetary Boom

The Deep Space Network, managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., is a worldwide network of antennas that supports interplanetary spacecraft missions, and some near-Earth missions. With antennas in Spain; near Canberra, Australia; and in California's Mojave Desert, the network has the ability to provide radio communications with spacecraft at all times. The three sites are spaced approximately one-third of the way around Earth from each other so they cover spacecraft in any direction as the world turns.

Among the missions supported by the network are the Mars Exploration Rovers that will land on Mars in January; the Stardust mission that will collect comet dust in January; the Cassini-Huygens mission that will probe the rings and moons of Saturn beginning in July; and the Genesis mission which is collecting solar wind particles for return to Earth in September.

"We have upgraded our network to accommodate the unprecedented level of activity this winter," said Peter Doms, manager of the Deep Space Network systems program at JPL. "It's the large number of these events that we need to support; that is the reason for these upgrades."

The Madrid antenna is the biggest piece of about $54 million worth of improvements to the network. "These upgrades will allow us to be right there when the missions need us," said Doms. Other upgrades include improving the capabilities of existing antennas at all three of the network's tracking complexes; modifying the antennas to "listen" to more than one spacecraft at a time; adding more powerful transmitters; replacing some older hardware and software with more reliable equipment; and adding a new navigation capability to help the Mars rovers land on their targets.

Each complex consists of several deep space stations equipped with large parabolic reflector antennas and ultra sensitive receiving systems that include a 70-meter-diameter (230-foot) antenna; a 34-meter-diameter (110-foot) high-efficiency antenna; at least one 34-meter (110-foot) beam waveguide antenna; and a 26-meter-diameter (85-foot) antenna.

"To give you an idea of how sensitive these antennas are, if we were to "listen" to one spacecraft in the outer solar system by Jupiter or Saturn for 1 billion years and add up all the signal we collected, it would be enough power to set off the flash bulb on your camera once," said Doms.

Mission projections for the period of November 2003 to February 2004 indicate the greatest need for increased communications capacity will be at the Madrid complex. The new antenna in Madrid will add about 70 hours of spacecraft-tracking time per week for the rovers and orbiters during the periods when Mars is in view of Madrid. The added hours represent a 33-percent increase from the station's current capacity of 210 hours per week.

In Australia, other NASA-funded upgrades were completed this summer on the Parkes Radio Telescope. Owned by the Australian Commonwealth Scientific and Industrial Research Organization, the 64-meter (210-foot) antenna is located near the town of Parkes, Australia. With upgrades to handle the current deep space transmission standards, Parkes will take on some of the Deep Space Network workload.

Parkes will provide backup support for a large number of critical mission events and will also provide coverage for missions that would otherwise receive less during periods of conflicts. The major improvement is adding a microwave system that allows for reception in the X-band frequency currently used by all missions. The amount of solid paneling on the Parkes antenna was also increased to offer better performance.

JPL is a division of the California Institute of Technology, also in Pasadena.

Information about the Deep Space Network is available online at:

http://deepspace.jpl.nasa.gov/dsn/index.html.