The Voyager probes started their journey to the edge of the unknown in 1977, and they’re still going strong decades later. NASA began receiving garbled communications from Voyager 1 earlier this year, prompting concerns that the legendary spacecraft was on the verge of a major system failure. Fortunately, NASA today says that it was able to resolve the problem with the 45-year-old spacecraft, but solving this enigma has lead to another that may be more difficult to solve.
Despite its name, Voyager 1 was the second of the probes to be launched. The “Grand Tour” of Jupiter, Saturn, Uranus, and Neptune was made possible by a rare alignment of the outer planets. Voyager 1 travelled directly to Jupiter and Saturn before entering interstellar space and passing Voyager 2. Voyager 1 became the first man-made object to escape the solar system in 2012.
This past May, NASA stated that something had gone wrong with the craft’s attitude articulation and control system (AACS). This system is in charge of keeping Voyager’s antenna pointing at Earth. If it fails, NASA may lose contact with the ageing probe for good. Surprisingly, the agency was still receiving good data while AACS was returning jumbled updates. Something was clearly wrong.
Communicating with a spacecraft this old is never going to be easy, but when you consider that Voyager 1 is more than 14.6 billion miles (23.5 billion kilometers) away, give or take a million miles, each communication takes nearly a full day to go to or from Voyager 1. NASA claims that the skewed AACS telemetry has been corrected after months of inquiry. The system itself was operational, but it began sending telemetry data via an inbuilt computer that had been known to fail for years.
A circuit board that is a component of the Voyager’s AACS subsystem.
The team tried a low-risk fix: notifying AACS to switch to the working computer, which worked flawlessly. Voyager 1 is now sending accurate data, which explains why the probe continued to operate despite the garbled orientation updates. However, it does not explain why AACS chose to use a broken machine in the first place.
NASA is still looking into what caused the mishap. The following step is to perform a full memory readout of the AACS, which may point to the triggering event. This should help engineers figure out what went wrong. The crew is “cautiously confident” that the fundamental issue may be identified and fixed while Voyager continues to explore.
Source : Thespaceacademy