Posted on 03/29/2018 5:54:55 PM PDT by Enchante
The thrusters aboard the Voyager 1 spacecraft just did what we thought was impossible. After 37 years of inactivity, NASA just received response from spacecraft 13 billion miles away, NASA said in a statement on its website. Voyager 1 is NASA’s farthest and fastest spacecraft. It was launched on September 5, 1977. Having operated for 40 years, 6 months and 14 days as of March 19, 2018, the spacecraft relies on small devices called thrusters to orient itself so it can communicate with Earth. These thrusters fire in tiny pulses, or “puffs,” lasting mere milliseconds, to subtly rotate the spacecraft so that its antenna points at our planet. Now, the Voyager team is able to use a set of four backup thrusters, dormant since 1980.
In a statement on its website, NASA said: “The Voyager team assembled a group of propulsion experts at NASA’s Jet Propulsion Laboratory, Pasadena, California, to study the problem. Chris Jones, Robert Shotwell, Carl Guernsey and Todd Barber analyzed options and predicted how the spacecraft would respond in different scenarios. They agreed on an unusual solution: Try giving the job of orientation to a set of thrusters that had been asleep for 37 years.”
“With these thrusters that are still functional after 37 years without use, we will be able to extend the life of the Voyager 1 spacecraft by two to three years,” said Suzanne Dodd, project manager for Voyager at NASA’s Jet Propulsion Laboratory, Pasadena, California.
“The Voyager flight team dug up decades-old data and examined the software that was coded in an outdated assembler language, to make sure we could safely test the thrusters,” said Jones, chief engineer at JPL.
In a further testament to the robustness of Voyager 1, the Voyager team completed a successful test of the spacecraft’s “trajectory correction maneuver” (TCM) thrusters on November 28, 2017. The last time these backup thrusters were fired up was in November 1980. Voyager project manager Suzanne Dodd anticipates that successful utilization of the TCM thrusters will extend the Voyager mission by an additional “two to three years”.
Voyager 1’s extended mission is expected to continue until around 2025 when its radioisotope thermoelectric generators will no longer supply enough electric power to operate its scientific instruments.
Send more Chuck Barry
Imagine the sensitivity of the instruments needed to detect that signal from Voyager.
Is the signal being received by the Hubble, one of those huge antennas on Earth? Curious.
Thanks. Was always curious what assembler code looked like.
“Is it the same as Machine Language?”
Closely related. Assembly language is a “pretty front end”, (sarcasm intended), to machine language.
Machine language is all 1’s and 0’s. Assembly looks something like:
MOV CX, 15
(Put a value of 15 in a register).
Up there. Somewhere...
Over the rainbow?
LOL
“...Is the signal being received by the Hubble, one of those huge antennas on Earth? Curious.” [poconopundit, post 82]
The Hubble Space Telescope senses near ultraviolet (300-400 nanometer wavelength), visible light (300-700 nanometer wavelength), and near infrared (750-1400 nanometer wavelength). Nothing to do with Voyager, nor other spacecraft.
Voyager 1 receives commands at a radio frequency of 2100 MHz, and sends responses at 2300 MHz and 8400 MHz. NASA’s Deep Space Network receives Voyager’s transmissions: antennas are all on Earth’s surface, at Goldstone (near Barstow, CA), near Madrid, in Spain, and near Canberra, in Australia.
Thank you. I learned something. It’s interesting.
“...Where this thing is, there’s no moisture, no change in temperature, no change in pressure, no bacteria, no oxygen - absolutely nothing which would cause rust or decay. They SHOULD work after 37 years!”
Voyager 1’s attitude control system has 16 main thrusters, and 8 backup thrusters, powered by hydrazine. There are also gryos, and referencing sensors, to allow the craft to determine its orientation and apply corrections, to keep the radio antenna pointing towards Earth.
I’d venture the opinion that the more-likely limitations here were the fuel supply, and the wear state of the gyros’ bearings. As mechanical devices, gyros have to spin to function, fuel tank seals must not leak, and valves must open and close. Structural integrity might have deteriorated after decades of bombardment by cosmic rays, gamma rays, and other radiation found in space. No machines have gone so far away, nor have any been subjected to cold-soak for so many years.
The microprocessors and their software have no such limitations - all they need is electrical power to keep going.
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