Voyager 2 Went Into Fault Protection Mode, But Engineers Brought it Back Online

NASA’s Voyager 2 spacecraft went into fault protection mode on Tuesday January 28th. The fault protection routines automatically protect the spacecraft in harmful conditions. Both Voyagers have these routines programmed into their systems.

After it happened, NASA engineers were still in communication with the spacecraft and receiving telemetry.

The fault protection stems from a maneuver attempted on January 25th. On that day, Voyager 2 was supposed to execute a scheduled rotation maneuver. The spacecraft rotates itself 360 degrees to calibrate one of its instruments, MAG, the triaxial fluxgate magnetometer. That instrument is investigating the solar wind boundary with the interstellar magnetic field and beyond.

NASA’s Voyager 2 Probe Enters Interstellar Space This illustration shows the position of NASA’s Voyager 1 and Voyager 2 probes, outside of the heliosphere, a protective bubble created by the Sun that extends well past the orbit of Pluto. Voyager 1 exited the heliosphere in August 2012. Voyager 2 exited at a different location in November 2018. Credit: NASA/JPL-Caltech

NASA says there was a delay in the maneuver, which caused two systems that draw a lot of power to be on at the same time. There’s a tight power budget on Voyager 2, because its radioisotope thermoelectric generators are running down. To protect itself, the spacecraft went into its fault-protection mode. In that mode, it shut down scientific instruments to make up for the power deficit. By January 28th, engineers had successfully shut down one of the two high-power-drawing systems, and turned its science instruments back on.

After that, they still weren’t receiving data from the spacecraft.

Voyager 2 is still running, but its power situation is precarious. Mission engineers are constantly evaluating the status of the power system, and they know that it’s losing about 4% of its power each year. A lot of power is needed to keep systems on the spacecraft from freezing, including fuel lines. If those lines froze, and broke, then Voyager 2 would no longer be able to point its antenna towards Earth, and the mission would effectively be over.

In this illustration, NASA’s Hubble Space Telescope is looking along the paths of NASA’s Voyager 1 and 2 spacecraft as they journey through the solar system and into interstellar space. Hubble is gazing at two sight lines (the twin cone-shaped features) along each spacecraft’s path. The telescope’s goal is to help astronomers map interstellar structure along each spacecraft’s star-bound route. Each sight line stretches several light-years to nearby stars. Credit: NASA, ESA, and Z. Levy (STScI).

Voyager 2 is about 18.5 billion kilometers (11.5 billion miles) away, so communicating takes a long time. It’s a 34 hour round trip for mission engineers to send a signal to the spacecraft and for the spacecraft to respond. So it’s taken several days to work through this scenario.

On January 29th, NASA sent out this Tweet:

So it looks like Voyager 2 is back on track, though we’re still waiting for things to get back to normal.

Voyager 2 is currently in interstellar space, having left the heliosphere in November 2018. In November 2019, three papers were published outlining what Voyager 2 found as it left the heliosphere. The spacecraft’s power is running down, and some of its instruments have been turned off. But it should have enough power to keep transmitting data.

NASA has said in the past that Voyager 2 has enough power to keep working until roughly 2020, so at some point in the near future, we may hear the spacecraft’s final transmission. Then it’ll head off into space, lost to humanity forever.


Evan Gough

Recent Posts

Brrr. JWST Looks at the Coldest Brown Dwarf

What are the atmospheric compositions of cold brown dwarf stars? This is what a recent…

11 hours ago

Cosmic Dust Could Have Helped Get Life Going on Earth

The early Earth didn't have many chemicals needed for life on its surface, but they…

20 hours ago

Odysseus Moon Lander Is Tipped Over But Still Sending Data

The bad news is that Intuitive Machines' Odysseus lander is tipped on its side after…

1 day ago

Finally! Webb Finds a Neutron Star from Supernova 1987A

I can remember seeing images of SN1987A as it developed back in 1987. It was…

2 days ago

A Capsule With Antiviral Drugs Grown in Space Returns to Earth

On Wednesday, February 21st, at 01:40 p.m. PST (04:40 p.m. EST), an interesting package returned…

2 days ago

The Sun Gets Feisty, Throwing Off Three X-Class Flares Within 24 Hours

The Sun is heading toward solar maximum (which is likely to be about a year…

2 days ago