The only radio antenna that can command the 43-year-old spacecraft has been offline since March, while it receives new hardware, but the work is about to end in February.
On October 29, 2020, mission operators sent a series of commands to NASAThe Voyager 2 spacecraft for the first time since mid-March. The spacecraft is flying alone, while the 70-meter-wide radio antenna used to speak to it is offline for repairs and updates. Voyager 2 returned a signal confirming that it received the “call” and executed the commands without any problems.
The Voyager 2 call was a test of new hardware recently installed on Deep Space Station 43, the only antenna in the world that can send commands to Voyager 2. Located in Canberra, Australia, it is part of the Deep Space Network (DSN) of NASA, a collection of radio antennas around the world used primarily to communicate with spacecraft that operate beyond the moon. Since the antenna went offline, mission operators have been able to receive health updates and scientific data from Voyager 2, but have been unable to send commands to the distant probe, which has traveled billions of kilometers from Earth since 1977 launch.
Among the updates to the DSS43, as the dish is known, are two new radio transmitters. One, which is used to speak to Voyager 2, has not been replaced for more than 47 years. The engineers also updated the heating and cooling equipment, power equipment and other electronics needed to operate the new transmitters.
The successful call to Voyager 2 is just an indication that the dish will be online again in February 2021.
“What makes this task unique is that we are working on all levels of the antenna, from the pedestal at ground level to the feedcones in the center of the dish that extend above 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 on track with the work we are doing.”
The Deep Space Network consists of radio antenna installations equally spaced around the globe in Canberra; Goldstone, California; and Madrid, Spain. The positioning of the three facilities ensures that almost all spacecraft with a line of sight to Earth can communicate with at least one of the facilities at any time.
Voyager 2 is the rare exception. In order to fly close to Neptunemoon Triton in 1989, the probe flew over the planet’s north pole. This trajectory deviated him to the south in relation to the plane of the planets, and he has been heading in that direction ever since. Now more than 11.6 billion miles (18.8 billion kilometers) from Earth, the spacecraft is so far south that it lacks a line of sight with radio antennas in the northern hemisphere.
Click on this interactive view of NASA’s Voyager 2 spacecraft and take a spin. Launched in 1977, the spacecraft is now more than 11.6 billion miles (18.8 billion kilometers) from Earth. Track your dramatic story through Eyes on the Solar System. Credit: NASA /JPL-Caltech
DSS43 is the only antenna in the southern hemisphere that has a transmitter powerful enough and that transmits the right frequency to send commands to the distant spacecraft. Voyager 2’s fastest twin, Voyager 1, took a different route Saturn and can communicate via antennas at the two DSN facilities in the northern hemisphere. The antennas must uplink commands for both Voyagers in a radio frequency range called the S band, and the antennas downlink spacecraft data to 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-wide (111-foot-wide) radio antennas at the Canberra facility can be used together to capture the signals that the Voyager 2 sends to Earth. The probe is sending scientific data from interstellar space, or 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 icy bodies beyond the orbit) of Neptune)
The DSS43 started 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 received a variety of updates and repairs since then. But the engineers who oversee the current work say this is one of the most significant renovations the dish has received and the longest that has been out of service in more than 30 years.
“The DSS43 antenna is a highly specialized system; there are only two other similar antennas in the world, so leaving the antenna off for a year is not an ideal situation for Voyager or many other NASA missions, ”said Philip Baldwin, operations manager for the Communications and Space Navigation Program (SCaN ) from NASA. “The agency made the decision to carry out these updates to ensure that the antenna can continue to be used for current and future missions. For an antenna almost 50 years old, it is better to be proactive than reactive with critical maintenance. “
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 critical role in the exploration efforts from Moon to Mars, ensuring communication and navigation support for precursor missions to Moon and Mars and Artemis manned missions. .
The Deep Space Network is managed by JPL for the SCaN Program, located at NASA Headquarters on the Human Exploration and Operations Mission Directorate. The Canberra station is administered on behalf of NASA by Australia’s national scientific agency, the Commonwealth Scientific and Industrial Research Organization.
Voyager spacecraft were built by JPL, which continues to operate both. JPL is a division of Caltech in Pasadena. Voyager missions are part of NASA’s Heliophysics System Observatory, sponsored by the Heliophysics Division of the Scientific Missions Directory in Washington.