NASA contacts Voyager 2 using the updated Deep Space Network antenna

On October 29, mission operators sent a series of commands to NASA’s Voyager 2 spacecraft for the first time since mid-March. The spacecraft flew by itself while the 70-meter (230-foot) wide radio antenna used to talk to it went offline for repairs and upgrades. Voyager 2 returned a signal confirming that it received the “call” and executed the commands without problems.

The call to Voyager 2 was a test of the new hardware recently installed on Deep Space Station 43, the only dish in the world capable of sending commands to Voyager 2. Located in Canberra, Australia, it is part of the Deep Space Network (DSN ) from NASA, a collection of radio antennas around the world used primarily to communicate with spacecraft operating beyond the moon. Since the dish went offline, mission operators have been able to receive health updates and science data from Voyager 2, but have not been able to send commands to the distant probe, which has traveled billions of miles from Earth since. its 1977 launch.

Among the updates to the DSS43, as the dish is known, there are two new radio transmitters. One of these, which is used to talk to Voyager 2, hasn’t been replaced for over 47 years. The engineers also upgraded the heating and cooling equipment, power equipment and other electronic components needed to operate the new transmitters.

The success of the call to Voyager 2 is just an indication that the dish will be back online in February 2021.

“What makes this task unique is that we are working at all levels of the antenna, from the pedestal at ground level to the feedcones in the center of the dish that extend over the edge,” said Brad Arnold, the DSN project manager. at NASA’s Jet Propulsion Lab in Southern California. “This test communication with Voyager 2 definitely tells us that things are in line with the work we are doing.”

Worldwide network

The Deep Space Network consists of radio antenna structures equally distributed throughout the world in Canberra; Goldstone, California; and Madrid, Spain. The placement of the three structures ensures that almost any spacecraft with a line of sight to Earth can communicate with at least one of the structures at any time.

Voyager 2 is the rare exception. To make a close flyby of Neptune’s moon Triton in 1989, the spacecraft flew over the planet’s north pole. That trajectory deflected it south from the plane of the planets, and it has been heading in that direction ever since. Now more than 11.6 billion miles (18.8 billion kilometers) from Earth, the probe is so far south that it has no line of sight to radio antennas in the Northern Hemisphere.

DSS43 is the only dish in the southern hemisphere that has a powerful enough transmitter and that transmits the right frequency to send commands to the distant spaceship. Voyager 2’s faster twin, Voyager 1, has taken a different route after Saturn and can communicate via antennas at the two DSN facilities in the Northern Hemisphere. The antennas must uplink commands to both Voyagers in a radio frequency range called the S-band and the antennas downlink the data from the spacecraft in a range called the X-band.

Although mission operators have not been able to command Voyager 2 since DSS43 went offline, the three 34-meter (111-foot) wide radio antennas at the Canberra facility can be used together to capture the signals that Voyager 2 sends. to the ground. The spacecraft sends scientific data from interstellar space, or from the region outside the heliosphere of our Sun, the protective bubble of particles and magnetic fields created by the Sun that surrounds the planets and the Kuiper belt (the collection of small frozen bodies beyond the orbit of Neptune).

DSS43 began operating in 1972 (five years before the launch of Voyager 2 and Voyager 1) and was only 64 meters (210 feet) wide at the time. It was expanded to 70 meters (230 feet) in 1987 and has since received a number of updates and repairs. But engineers overseeing the work in progress say this is one of the most significant renovations the dish has received and the longest it has been offline in over 30 years.

“The DSS43 antenna is a highly specialized system; there are only two other similar antennas in the world, so having the antenna turned off for a year is not an ideal situation for Voyager or many other NASA missions,” said Philip Baldwin. , operations manager for NASA’s Space Communications and Navigation (SCaN) program. “The agency has decided to conduct these updates to ensure that the antenna can continue to be used for current and future missions. For an antenna that is nearly 50 years old, it is better to be proactive than reactive with critical maintenance.”

The repairs will benefit other missions, including the Mars Perseverance rover, which will land on the Red Planet on February 18, 2021. The network will also play a pivotal role in the moon-to-Mars exploration efforts, providing communication and navigation support for both. Moon and Mars precursor missions and manned Artemis missions.