NASA Techs Are Working Quickly to Repair Voyager 1

A mistake in the computer system has cast doubt on the destiny of humanity’s most distant space probe.

Voyager 1 is still alive out there, barreling into the cosmos more than 15 billion miles away. However, a computer problem has kept the mission’s loyal support team in Southern California from knowing much more about the status of one of NASA’s longest-lived spacecraft.

Voyager 1’s capacity to transmit back telemetry data, such as measurements from the craft’s science equipment or fundamental technical data about how the probe was functioning, was hampered by the computer fault that appeared on November 14. Consequently, the crew is blind to important details pertaining to the craft’s power, propulsion, and control systems.

“Regaining it would be the greatest miracle of all time. In an interview with Ars, Suzanne Dodd, the project manager for Voyager at NASA’s Jet Propulsion Laboratory, stated, “We certainly haven’t given up.” “We can try different things. But in my whole time as a project manager, this is by far the most severe.”

In 2010, Dodd was appointed project manager for NASA’s Voyager mission, where he was in charge of a small team of engineers who were in charge of the interstellar journey of humanity. With a speed of 38,000 miles per hour (17 kilometers per second), Voyager 1 is the furthest-traveling spacecraft in history.

Not quite as far away is Voyager 2, which launched 16 days before Voyager 1 in 1977. It traversed the solar system more slowly, passing through Jupiter, Saturn, Uranus, and Neptune, while Voyager 1 accelerated during a close encounter with Saturn to pass its sister ship.

NASA has been using Voyager’s equipment to research interstellar plasma environment, magnetic field, and cosmic rays for the past couple of decades. They have stopped snapping photos. Both probes have crossed the heliopause, the point at which solar particle emissions enter the interstellar medium.

At this time, there are no other spacecraft in operation that are investigating interstellar space. After passing Pluto in 2015, NASA’s New Horizons spacecraft is expected to arrive in interstellar space by the 2040s.

Modern Times Half a Century Ago

The probe’s Flight Data Subsystem (FDS), one of three computers on board, along with a central computer for command and control and another device that manages attitude control and pointing, is the source of the most recent issue with Voyager 1.

The FDS is in charge of gathering scientific and engineering data from the spacecraft’s sensor network and integrating it into a single binary data package, or sequence of 1s and 0s. The Telemetry Modulation Unit, a distinct component, is responsible for transmitting the data package back to Earth via Voyager’s 12-foot (3.7-meter) dish antenna.

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NASA reported that in November, Voyager 1’s data packages showed a repeating sequence of 1s and 0s, as though it was stuck. According to Dodd, JPL engineers have been attempting to determine the root of the issue for almost three months. The FDS appears to be experiencing issues with “frame syncing” data, and she stated that the technical team is “99.9 percent sure” that this is where the issue started.

As of right now, the ground team feels that a little amount of corrupted memory in the FDS is the most likely cause of the issue. But due to the computer glitch, engineers are unable to access comprehensive Voyager 1 data that could help them identify the source of the problem. “It’s likely somewhere in the FDS memory,” Dodd stated. “Something got corrupted or flipped. However, we are unable to locate the FDS memory corruption without the telemetry.”

Computing was a revolutionary field when Voyager’s Flight Data Subsystem was created fifty years ago. It was the first spacecraft computer to use volatile memory. Every Voyager spacecraft had two FDS processors at launch, but Dodd claims that Voyager 1’s backup FDS failed in 1981.

Since November, the only communication Voyager 1’s Earthbound engineers have had is a carrier tone, which essentially indicates to them that the spacecraft is still alive. No additional significant issues are apparent. Voyager 1 is getting directives uplinked from Earth, as indicated by changes in the modulation of the carrier signal.

“Unfortunately, we haven’t cracked the nut yet, or solved the problem, or gotten any telemetry back,” Dodd stated.

Taking the Binders Off

The ground crew of Voyager 1 intends to send commands to Voyager 1 in the coming weeks in an attempt to pinpoint the location of the alleged faulty memory within the FDS computer. One of the concepts is toggling the computer to run in multiple modes, similar to the FDS’s 1979 and 1980 operating settings when Voyager 1 passed past Jupiter and Saturn. The developers on Voyager believe that switching between data modes would highlight any areas of the FDS memory that require correction.

This is far more intricate than it first appears to be. One reason is that Voyager 1’s data modes, which engineers might instruct it to enter, haven’t been in operation for at least 40 years. For decades, no one has considered utilizing Voyager’s flight data computer in this way.

The public visibility of Voyager 1 and 2 is disproportionate to the resources NASA devotes to maintaining the spacecraft. On average, less than twelve individuals are involved in the Voyager expedition. Since the computer issue first surfaced in November, this number has somewhat increased. To assist in troubleshooting the malfunction, a small “tiger team” consisting of about eight specialists in flight data systems, software, and spacecraft communications has been assigned.

“Not to be morose, but a lot of Voyager people are dead,” Dodd stated. Thus, the individuals who constructed the spaceship are no longer living. We do have a fair amount of material, but most of it is on paper, so in order to obtain records, you must conduct this archeology dig.”

Think of it like searching through an old car’s owner’s manual. The worn pages of the book are most likely fraying. That is similar to what some of the Voyager engineers—who weren’t even born when the voyage started—are going through right now.

“We have sheets and sheets of schematics that are paper, that are all yellowed on the corners, and all signed in 1974,” Dodd stated. “People are observing them because they are pinned up on the walls. How to gather the information you need to be able to discuss the important choices or potential problems is a whole other tale.”

For the engineers of Voyager, this is a routine task. Over the past few years, the JPL core team for the mission has examined old records in an effort to solve less critical computer issues and create a new protocol for both spacecraft’s engines that will prevent residue from building up in fuel lines.

Although redundancy is a favorite feature of spacecraft engineers, backups are no longer an option on the Voyagers. This implies that a single component failure in any one area of the spacecraft might end the mission. The nuclear batteries that power both spacecraft are depleting yearly due to the degradation of their plutonium power sources. The dwindling power will compel NASA to begin shutting down the equipment on every spaceship by the end of the 2020s.

The majority of NASA’s current solar system exploration missions use ground-based simulators to test procedures and orders before deploying them to the actual spacecraft. This exercise can identify commanding mistakes that might jeopardize a mission.

“Managing Voyager is a challenging task,” Dodd remarked. “For this, we don’t have any kind of simulator. There isn’t a hardware simulator here. There isn’t a software simulator available. There’s no simulator with the FDS, no hardware where we can try it on the ground first before we send it. So that makes people more cautious, and it’s a balance between getting commanding right and taking risks.”

The age of Voyager 1 is also known to the managers. It is using borrowed time to operate. “So we don’t want to spend forever deciding what we want to do,” Dodd stated. “Something else could not work. It’s possible that the thrusters will malfunction. We can’t hesitate to act morally even though we want to do the right thing. We need to look at things methodically and logically, make a decision, and go for it.”

Operators at JPL will have to wait more than 45 hours to hear back when it comes time to send up fresh commands in an attempt to salvage Voyager 1. NASA has to use the largest 230-foot (70-meter) antenna at a Deep Space Network monitoring point in Australia because of the spacecraft’s great distance and position in the southern sky. This antenna is one of the most in-demand on the network.

“The data rates are very low, and this anomaly causes us not to have any telemetry,” Dodd stated. “We’re kind of shooting in the blind a little bit because we don’t know what the status of the spacecraft is completely.”

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