The Voyager 1 spacecraft, nearly 25 billion km from Earth, continues to have problems due to the onboard power supply increasingly running out.
Voyager 1 is flying in interstellar space. Image: Sci Tech Daily
NASA engineers have successfully restored communication with Voyager 1 and the spacecraft is operating normally after dwindling power supplies caused a loss of signal for weeks. The problem began in October when the aging probe automatically switched from its X-band radio transmitter and began relying on its much weaker S-band radio transmitter to communicate with the crew. mission on Earth. As the spacecraft furthest from Earth, Voyager 1 is currently exploring interstellar space at a distance of 24.9 billion km, according to CNN.
The probe automatically switched transmitters when the onboard computer determined Voyager 1 had too little power left after the crew gave the command to turn on one of the heaters. The unexpected change prevented engineers from receiving information about Voyager 1’s status, as well as scientific data collected by the spacecraft’s instruments, for nearly a month. With some clever workarounds to the problem, the team in charge successfully transferred Voyager 1 and its X-band radio transmitter and received daily data again from mid-November.
“The probe duo was never really designed to operate like this, and the team learns new things every day,” said Kareem Badaruddin, Voyager mission manager at NASA’s Jet Propulsion Laboratory. in Pasadena, California, said. “Fortunately they were able to fix this problem.”
But this is just one of many challenges the mission team has faced in recent years as Voyager 1 and its twin Voyager 2 probes continue to explore space more than 47 years after liftoff. The pair of probes launched a few weeks apart in 1977 lasted much longer than the original mission, designed to fly by the solar system’s largest planets over four years. Currently, they are flying in interstellar space and are the only spacecraft to operate beyond the heliosphere, the Sun’s bubble of magnetic fields and charged particles that extends across Pluto’s orbit.
Both spacecraft operate thanks to heat from decaying plutonium being converted into electricity. Each year, the probe loses about 4 watts of power, according to NASA, equivalent to a small energy-saving light bulb. The team began shutting down any systems that weren’t critical to the probe’s flight five years ago. Some systems include heaters that help scientific equipment maintain operation at the right temperature. But what surprised the engineers was that all the devices continued to function, even at temperatures lower than they had been tested for decades before.
Occasionally, the engineering team sends commands to Voyager 1 to turn on some heaters and warm parts damaged by decades of radiation, according to Bruce Waggoner, Voyager mission insurance manager. Heat can help reverse radiation damage, which reduces the performance of spacecraft components. But the command transmitted to the heater on November 16 activated the ship’s automatic anti-fault system. If the spacecraft uses more power than is available, it automatically shuts down unnecessary systems to conserve energy. The team in charge discovered the latest problem when it failed to receive a response signal from the spacecraft on October 18.
The two Voyager probes turned off all non-essential systems except the science equipment, an error-proof system that turned off the X-band transmitter and switched to the S-band because the latter uses less power. Voyager 1 has used X-band transmitters for decades, but S-band has not been used since 1981 because the signal is much weaker. The team must search for an extremely weak S-band signal before they can restore contact with the spacecraft.
On November 7, engineers successfully transmitted a command to the Voyager 1 spacecraft to switch back to the X-band transmitter and begin collecting scientific data on November 18. They are actively reinstalling the system used to synchronize Voyager’s three computers. This is one of the final missions to ensure Voyager returns to the way it was before the transmitter problems occurred.
The transmitter change is just one of several initiatives NASA has used to overcome communications challenges with the aging spacecraft this year, including firing thrusters to help Voyager’s antenna stay pointed. toward Earth and develop a solution to a computer glitch that interrupted the probe’s flow of scientific data back to Earth for months.
The Voyager team has computer models that help them predict how much electricity the spacecraft’s heaters and equipment use. But the fact that the heater turned on and activated the anti-error system is a signal that this probe is reaching the end of its life cycle and faces a more uncertain future.