A radio antenna in Australia in dire need of upgrades will be offline for the next 11 months, during which time NASA mission controllers won’t be able to transmit commands to the Voyager 2 probe, which is currently in interstellar space.
Measuring 70 metres wide and standing 20 stories high, the DSS43 radio antenna at the Canberra Deep Space Communication Complex is currently the only system on Earth capable of communicating with NASA’s Voyager 2 probe, which is currently 18.5 billion kilometres from Earth. The Canberra facility is a critical component of NASA’s Deep Space Network (DSN), but it’s now 40 years old and in need of repair and modern upgrades.
Trouble is, the scheduled maintenance, which is set to start this month and last until January 2021, means NASA controllers will temporarily be unable to transmit commands to Voyager 2, according to a NASA Jet Propulsion Laboratory press release. Thankfully, the probe will still be able to send information to us during this time, so it’ll continue to transmit valuable scientific data from its fascinating location beyond the heliosphere.
Should something go wrong over the course of the next 11 months, however, NASA won’t be able to transmit the required remedy.
That something could go wrong between now and January 2021 is a troubling possibility. Just a few weeks ago, for example, Voyager 2 failed to execute a required spin manoeuvre, causing the spacecraft to shut down its science instruments to conserve energy. NASA, after diagnosing the problem, issued a series of commands, restoring Voyager 2 to normal operating conditions.
That said, NASA has placed Voyager 2 in a kind of quiet mode, to prevent something like this from happening during the coming months.
“We put the spacecraft back into a state where it will be just fine, assuming that everything goes normally with it during the time that the [Canberra] antenna is down,” explained Suzanne Dodd, Voyager project manager and JPL director for the Interplanetary Network, in the press release. “If things don’t go normally—which is always a possibility, especially with an ageing spacecraft—then the onboard fault protection that’s there can handle the situation.”
It may seem surprising that only one radio antenna in the world is capable of talking to Voyager 2. The DSN currently consists of three stations, in Australia, California, and Spain. Collectively, these facilities allow NASA to communicate with deep space probes at any point during Earth’s rotation. Trouble is, Voyager 2 is dipping in a downward direction relative to Earth’s orbital plane. This means the probe is only accessible from our planet’s southern hemisphere, hence the importance of the Australian facility.
Another reason has to do with the now-outdated technology that was used for Voyager 2, which was launched in 1977. The spacecraft can only receive S-band transmissions. The Canberra Deep Space Communication Complex is the only facility in the southern hemisphere currently capable of transmitting across the S-band at the required strength and frequency.
The risk to Voyager 2 is real, but repairs and upgrades to the Canberra Deep Space Communication Complex are most crucial. It’s a nonstop, 24-hours-a-day, 365-days-per-year facility, but at four decades old, it’s becoming “increasingly unreliable,” as NASA noted in its press release.
The upgrades will reduce the risks of unplanned outages, make the system more reliable, and add state-of-the-art tech to improve the Voyager 2 mission as well as other ongoing and future projects, such as the NASA’s Mars 2020 Perseverance rover, the upcoming Artemis mission to the Moon, and a future mission to Mars.
NASA will steadily monitor signals from Voyager 2 over the course of the next 11 agonising months. Should a problem occur, however, mission controllers will only be able to watch on in dismay and hope that, when the Canberra facility returns to full capacity, they’ll still be able to talk to this historic probe.