Voyager 1 Mission Engineers Successfully Fix Clogged Fuel Line

On August 27, 2024, NASA’s Voyager 1 mission engineers achieved a remarkable feat by fixing a clogged fuel line in the spacecraft, which is currently 24.6 billion kilometers away from Earth.

The fuel line is crucial for Voyager 1’s thrusters to point its antenna toward Earth, enabling the spacecraft to receive commands and send data from its scientific sensing equipment.

The Challenge of Fixing a 47-Year-Old Spacecraft

While clogged fuel lines can be solved by switching to another propulsion system, this was not a straightforward solution for Voyager 1. The spacecraft, built in the 1970s, has been in space for over 47 years, and many of its systems have been shut down to conserve energy and extend its mission life.

Voyager 1’s propulsion system consists of two directional thrusters used for maneuvering and taking pictures of planets, and another set of adaptive orbital thrusters for adjusting the spacecraft’s position in space.

A Complex Solution

When NASA decided to extend the Voyager 1 mission after its close flyby of Saturn in 1980, it used directional thrusters as the main thrusters to point the antenna toward Earth. Later, in 2002, it switched to another directional thruster system, and in 2018, it began using an adaptive orbital thruster system.

Voyager 1 uses liquid hydrazine in its three thrusters, which is converted into a gas to provide a gentle push to orient its antenna toward Earth as it speeds away at 16.9995 kilometers per second.

However, over decades of continuous operation, the fuel line started clogging with silicon dioxide, leaving only 0.035 millimeters of space for the liquid hydrazine to be delivered.

A High-Risk Solution

Engineers decided to switch back to directional thrust, which presented significant challenges and risks. To conserve energy, Voyager 1’s heaters and non-essential equipment were turned off, exposing the spacecraft to extremely cold temperatures.

Engineers had to find a way to turn on the heater to raise the temperature of the propulsion system without risking damage. However, turning on the heater required a significant amount of energy, which meant shutting down some systems to compensate.

A Successful Outcome

The mission team on Earth made it clear that they would not turn off the scientific exploration equipment, as there was a risk that it would not work again. Instead, engineers decided to turn off the main heater of Voyager 1 for an hour to use the energy to operate the heaters and warm up the propulsion system.

Eventually, the mission team received data from Voyager 1 confirming that the steering thrusters were operational again. It takes over 45 hours to send a round-trip signal at the speed of light to allow Voyager 1 to precisely point its dish toward Earth.

Voyager project manager Suzanne Dodd emphasized the importance of data analysis for the Voyager 1 and Voyager 2 spacecraft, which are over 47 years old and currently on a mission in the space between the stars.

As Voyager 1 continues to move away from Earth at 16.9995 kilometers per second, the mission team is working to find solutions to extend the spacecraft’s mission life and enable it to send data back to Earth for as long as possible.