On September 5, 1977, NASA launched a space probe named Voyager 1 into the universe. Nearly 45 years later, to the astonishment of astronomers around the world, this bird still comes alive as it travels as far as Pluto.
In fact, Voyager 1 has traveled far beyond the frontiers of our solar system — and is now giving out strange readings that scientists are striving to understand.
The mystery probably has something to do with the fact that Voyager 1 is the farthest artificial object in space. At a distance of 14.5 billion miles from Earth, Voyager 1 passed through the heliosphere in 2012. The sun is the barrier that separates the solar wind from the interstellar medium, or all the matter and radiation found in space between the different solar systems in the galaxy. This means that Voyager 1 is literally located in the interstellar void of the Milky Way.
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This may have something to do with the reason why in Jimmy Carter’s era the machine sends signals that can best be described as strange.
“The interstellar explorer operates normally, receiving and carrying out commands from Earth, along with collecting and returning scientific data,” NASA explained on its website. “But the readings from the Expression Probe Position and Control System (AACS) do not reflect what is actually happening on board.”
“We’re also in interstellar space – a highly radioactive environment that no spacecraft has ever flown into.”
More specifically, NASA explained, the AACS keeps the spacecraft’s antenna pointed at Earth so that it transmits the data back to our planet. On the surface, the AACS system seems to keep working, but all the telemetry data it sends back is invalid, like looking like it was randomly generated or physically impossible. This raises questions.
“An enigma like this is kind of on par with the cycle at this point in the Voyager mission,” Susan Dodd, Voyager 1 and 2 project manager at NASA’s Jet Propulsion Laboratory in Southern California, said in a statement. “The spacecraft is approximately 45 years old, which is far beyond what mission planners expected.”
Dodd added, “We’re also in interstellar space – a highly radioactive environment where no spacecraft has flown before. So there are some big challenges for the engineering team. But I think if there is a way to solve this problem with AACS, our team will find it.”
RELATED: The Voyager 1 probe is now so far away that it can hear the background ‘hum’ of interstellar space.
This wouldn’t be a quick fix. The signal from Earth currently takes 20 hours and 33 minutes to reach Voyager 1 and vice versa. Both the Voyager 1 and Voyager 2 twins suffer from a dwindling power supply, forcing engineers to turn off parts to save as much as possible. Some hope that Voyager 1 will be able to continue transmitting data until 2025, after which thermoelectric radioisotope generators (RTGs) will not be able to summon enough power to keep their equipment running.
Even if Voyager 1 proves to be in its final stages sooner than expected, it still has a historic flight. As it flew by gas giants Jupiter and Saturn, as well as Saturn’s largest moon Titan, it obtained detailed images and unprecedented amounts of data. The Voyager probe is known to contain a so-called “golden record” (actually two phonograph records) that preserve Earth’s culture for any extraterrestrial beings that might stumble upon and ingest it. The gold-plated discs include everything from the sounds of nature to the music of Wolfgang Amadeus Mozart and Chuck Berry.
In fact, the Voyage 1 probe is now so deep in space that astronomers can literally hear the “hum” that our solar system produces as the spacecraft travels outside it.
Stella Koch-Uker, a doctoral student in the Department of Astronomy and the Cornell Center for Astrophysics and Planetary Science, told Salon at the time about the study by the lead author. “We are observing the faint, continuous buzz of interstellar gas.”
One of the senior authors — James Cordes, a professor of astronomy at Cornell University — told Salon that “the interstellar medium is like calm or gentle rain. In the case of a solar flare, it is like discovering a lightning explosion in a thunderstorm and then returning as light rain.”
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