NASA's Voyager 1 spacecraft has fired a set of four control thrusters for the first time in 37 years, giving the Long duration probe a new way to point your cruise to interstellar space 13 billion miles from Earth.
The reserve rockets were originally designed to help the Voyager 1 spacecraft aim its instruments at planets and moons as it travels through the solar system.
Launched in September 1977, the plutonium probe found Jupiter and its moons in March 1979, then flew through Saturn in November 1980, before heading north from the plane of the ecliptic, the disk in the that the planets of the solar system reside. The identical Voyager 2 spacecraft visited Jupiter and Saturn, then went on to explore Uranus and Neptune.
The main thrusters of Voyager 1 have been degrading in recent years, NASA said in a statement. The small rockets generate about 0.2 pounds of thrust, roughly equivalent to the weight force of a deck of cards.
The MR-103 propellers, provided by Aerojet Rocketdyne, are designed to pulse in order to rotate the spacecraft and keep its 12-foot (3.7-meter) antenna pointing to Earth, but engineers have recently noticed that More shots were needed, indicating that the jets were losing some of their performance.
The ground controllers sought a solution and decided to try a separate rocket with four identical MR-103 "trajectory correction maneuver" or TCM, propellers on the back of the spacecraft that were used to push Voyager 1 and keep it ongoing during the flybys earlier in the mission.
The TCM thrusters were last fired on November 8, 1980, when approaching Saturn, and Voyager 1 used the miniature rocket engines in a more continuous firing mode, not individual pulses, depending on the needs of NASA.
Tuesday, November 2, 8, 2017, Voyager engineers fired the four TCM thrusters for the first time in 37 years and tested their ability to steer the ship with 10 millisecond pulses, "NASA said in a statement. "The team waited anxiously when the test results traveled through space, taking 19 hours and 35 minutes to reach an antenna in Goldstone, California, which is part of NASA's Deep Space Network.
"Here on Wednesday, November 29, they learned that the TCM thrusters worked perfectly, and as well as the attitude control boosters," the statement said.
The engineers had to do detective work to make sure that the propellers could be tested safely.
The Voyager flight team discovered data from decades ago and examined the software that was encoded in an obsolete badembly language, to ensure we could test the propellers safely, "said Chris Jones, chief engineer of the Propulsion Laboratory. NASA Jet.
Controllers at JPL plan to switch to full-time TCM thrusters in January, restoring the other Voyager 1 rockets. The spacecraft will have to light a heater on each of the four TCM thrusters, that would further deplete the decomposing plutonium energy source of Voyager 1.
Voyager 1 will return to its other propellants once the probe no longer has enough power for the heaters, authorities said.
"With these propellers that continue to operate after 37 years without use, we can extend the life of the Voyager 1 spacecraft in two or three years, "said Suzanne Dodd, manager of Voyager project at JPL.
Each Voyager spacecraft carries four TCM thrusters and 12 small attitude control rockets, divided into two redundant chains of six thrusters. Voyager 1 was already operating in its back-up branch of attitude control thrusters.
NASA will probably do a similar test of the TCM thrusters of Voyager 2, which could be used if the spacecraft's attitude control propellers are degraded further in the future.
Voyager 1 is the most distant object made by man, and scientists announced in 2013 the crossing of the border ship between the influence of the sun and interstellar space, making it the first mission to explore the void between the stars. The plutonium generator of the spacecraft should produce enough energy to keep it running until around 2025.
Scientists expect Voyager 2 to cross into interstellar space in a few years, heading in a different direction from the sun.
NASA Pioneer 10 and 11 spacecraft are also in interstellar space, but they no longer have enough power to contact the Earth, and the New Horizons spacecraft is on a trajectory to leave the solar system after their encounter with Pluto.
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