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NASA Power Hack Extends 45-Year Voyager 2 Mission Even Longer

217 points by taubek 4y ago

e12e 4y ago
Does anyone know if JPL have "local copies" of Voyager 1 and 2 that they can test things like this hack on? Or do they just plan it out and try on the probes themselves?
hi 4y ago
JPL Press Release: https://www.jpl.nasa.gov/news/nasas-voyager-will-do-more-science-with-new-power-strategy https://www.jpl.nasa.gov/news/nasas-voyager-will-do-more-sci...
bruce511 4y ago
Everything about Voyager is just mind-blowing. These are 45 year old electronic devices, using 70's tech, with zero maintenance, operating 22 light hours away. At that range they can still send messages detectable on earth. 9 out of 10 instruments are still working. People just leaving school when they launched are already retired. This is one time when the adage "they don't make them like they used to" is well applied. Hat tip to all involved.
- hulitu 4y ago
  > Everything about Voyager is just mind-blowing. These are 45 year old electronic devices, using 70's tech, with zero maintenance, operating 22 light hours away. No, what is mind blowing is that we are not able to do it again.
  - jfengel 4y ago
    We did do it again. We got New Horizons out to Pluto a lot faster, without the aid of the remarkable alignment that made Voyager possible. We keep exploring the solar system. There's no reason to repeat the same experiments. We've explored the planets in a lot more depth, and just launched even more.
- derrasterpunkt 4y ago
  Voyager 2 had 11 instruments. 5 are still active. But still, it is a remarkable piece of technology.
- schmichael 4y ago
  Agreed, but I believe Voyager is 18.5 light hours away, not 22. The article says it is 20 billion km away which is 18.5 light hours. However the article also states signals take 22 hours to reach the spacecraft. Do radio waves travel slower than the speed of light even in the vacuum of space? I assume the waves do not spend the extra 3.5 hours in Earth's atmosphere!
  - ars 4y ago
    The article is rounding up, and the parent comment is talking about Voyager 1. Specifically: Voyager 1 is 23.8 billion km (23.8 Tm), and Voyager 2 is 18.3 Tm.
    - dylan604 4y ago
      For those that might not be aware, Voyager 2 launched before Voyager 1, so the distance discrepancy is not due to the further one being launched first
      - bragr 4y ago
        Voyager 2 was launched first but on a less direct trajectory out of the system which allowed it to visit Uranus and Neptune. Voyager 1 is going much faster https://voyager.jpl.nasa.gov/mission/status/ https://voyager.jpl.nasa.gov/mission/status/
  - urubu 4y ago
    There is an effect called dispersion, which causes different frequencies of electromagnetic radiation to travel through a medium at different speeds (lower frequencies => slower). It's strong enough to be noticeable in the case of pulsars (but probably insignificant inside the solar system).
  - sosodev 4y ago
    I think it's because space isn't a perfect vacuum. The interstellar medium is a mix of gas and dust that slow down and weaken the signal. That effect is known as dispersion. With that said, it seems like the article might be inaccurate. That discrepancy seems too large to be explained by dispersion. I'm not an expert though. edit: I think the author got Voyager 1's distance mixed up with Voyager 2. Voyager 1 is ~22 (21.6) light hours away.
- shagie 4y ago
  Btw, you can see the occasional communication with Voyager at https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html As I write this, one of the dishes at Madrid just went to "Setup" for communication with VGR1. (late edit - some of the stats from the 'more info' at the bottom of the spacecraft panel) DATA RATE 160.0 b/sec POWER RECEIVED -160 dBm (1.0 x 10-22 kW)
- enkid 4y ago
  I mean, with a few notable exceptions, NASA's scientific missions have an amazing record of lasting much longer than they were designed for, Hubble and the Mars rovers & helicopter being amazing feats of lasting longer then they should.
croutonwagon 4y ago
Heres another article I read today that had some specifics. They are disabling a voltage regulator to save power and prioritize the science instruments as a calculated risk. https://phys.org/news/2023-04-nasa-voyager-science-power-strategy.html https://phys.org/news/2023-04-nasa-voyager-science-power-str... >In search of a way to avoid shutting down a Voyager 2 science instrument, the team took a closer look at a safety mechanism designed to protect the instruments in case the spacecraft's voltage—the flow of electricity—changes significantly. Because a fluctuation in voltage could damage the instruments, Voyager is equipped with a voltage regulator that triggers a backup circuit in such an event. The circuit can access a small amount of power from the RTG that's set aside for this purpose. Instead of reserving that power, the mission will now be using it to keep the science instruments operating. >Although the spacecraft's voltage will not be tightly regulated as a result, even after more than 45 years in flight, the electrical systems on both probes remain relatively stable, minimizing the need for a safety net. The engineering team is also able to monitor the voltage and respond if it fluctuates too much. If the new approach works well for Voyager 2, the team may implement it on Voyager 1 as well.
jacquesm 4y ago
If there is on thing this demonstrates then it is that the combination of good documentation and clever engineering can go a long, long way.
evan_ 4y ago
I'm amazed that they're able to disable a voltage regulator remotely. Did they just build in relays for every single component in case they wanted to rewire everything on the fly or was this something they specifically knew they might want to do 45 years ago?
- sgtnoodle 4y ago
  Yeah, I'd say it's actually pretty common to make spacecraft avionics as remotely switchable as possible. For one thing, there's likely to be a considerable amount of redundancy so that a single component failure doesn't ruin your whole mission. It's good practice to have a way to isolate any component that is anticipated to fail. FDIR is a known acronym: fault detection, isolation and recovery.
- CodeWriter23 4y ago
  They probably implemented fail-safe relays with circuitry to disengage automatically under hazardous conditions but also controlled remotely.
- foobarian 4y ago
  Also I assume there isn't a web service running there with a "enable/disable" endpoint to control stuff. Wonder what the control stack looks like. Turned up this from https://voyager.gsfc.nasa.gov/Library/DeepCommo_Chapter3--141029.pdf https://voyager.gsfc.nasa.gov/Library/DeepCommo_Chapter3--14...: > The signal consists of 16-bps, Manchesterencoded commands, biphase modulated onto a squarewave subcarrier frequency of 512 hertz (Hz). There are references to fuller descriptions of the command set but I haven't found them yet.
  - stouset 4y ago
    I can't help but wonder how possible it would be (or would have been at some point in the past) for a person with evil intent to send unauthorized commands to these probes. How are signals authenticated? At this point, is it just that there are only a handful of parties capable of sending a strong enough radio signal to a precise-enough location in space, and who know the position of these probes to the degree of accuracy required?
itslennysfault 4y ago
Ya know...... Considering how long it takes these things to get to deep space we probably should've kept the Voyager program going. By that, I mean we should've continued iterating and launching Voyager probes. If we launched one every 2 or even 5 years we'd have between 22 and 9 additional probes heading into deep space a couple years apart. Each with slightly better tech than the previous.
- kristianp 4y ago
  Agreed. Every time I see a story about the Voyagers, I wonder why a follow-up hasn't been done that is much faster and more capable.
  - thatcherc 4y ago
    It's the same reason the Voyagers launched in the late 70s - the Grand Tour configuration of the planets [0]. The outer planets align in a way that lets you chain together several gravity assists to achieve high enough speeds to escape the solar system. The trick is that configuration only occurs every 175 years. I don't think we have any space vehicles right now that could produce that same kind of delta-v with their own chemical/electrical/nuclear power. [0] - https://en.wikipedia.org/wiki/Grand_Tour_program https://en.wikipedia.org/wiki/Grand_Tour_program
    - skykooler 4y ago
      It's feasible to do an alternate route to the outer solar system by using an ion engine, dropping the perihelion down below Venus's orbit and then using a Venus -> Earth gravity assist chain with the ion engine going the whole time. The downside is that this is a more lengthy process than the Grand Tour route, and you have to do all your maneuvers in the inner solar system because ion engines draw a lot of electrical power and solar panels get very weak once you get past Mars or so.
  - CamperBob2 4y ago
    Probably because it made more sense to use the general information obtained from the Voyagers to design probes with specific capabilities to explore specific planets. The Cassini/Huygens mission might be a possible example.
FridayoLeary 4y ago
The probes get their power from the decay of a plutonium isotope. The question is why can't we find applications for this technology on earth, for example to power your house or something?
- allisvancity 4y ago
  They evidently used to use radiothermal generators (RTGs) as the power source for some pacemakers. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#History https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge... Plutonium is nasty & expensive stuff, however. That puts some pretty severe limitations on its usefulness for domestic purposes.
  - 1letterunixname 4y ago
    RTGs in humans: not for a long time.
- deleted 4y ago
  [deleted]
- neaden 4y ago
  It's a very small, but stable, amount of power generated given the amount of plutonium and the costs/risks of it it's not really worth it for anything else. Geothermal for instance for a home would make much much sense.
- speed_spread 4y ago
  The USSR did that for a while. It didn't end well for some people. https://en.m.wikipedia.org/wiki/Lia_radiological_accident https://en.m.wikipedia.org/wiki/Lia_radiological_accident
  - FridayoLeary 4y ago
    Thanks for that source. Maybe it's impractical for domestic use but it looks like they found uses for it in isolated locations for industrial purposes. Obviously it needs to be handled responsibly.
7373737373 4y ago
Video recommendation: How To Contact The Voyager 2 Probe (https://www.youtube.com/watch?v=FzRP1qdwPKw https://www.youtube.com/watch?v=FzRP1qdwPKw) and Pinging The Voyager 2 Probe (https://www.youtube.com/watch?v=1rCrfQUcXDI https://www.youtube.com/watch?v=1rCrfQUcXDI) by EEVDiscover
- noodlesUK 4y ago
  Thank you so much for these links. These are much more detailed videos than I expected going over the RF and antennas involved.
- 1letterunixname 4y ago
  Dave! :D
  - cwillu 4y ago
    Don't turn it on, take it apart!
    - 1letterunixname 4y ago
      Correction: apaaat
sammyjoe72 4y ago
What blows my mind is that even after 40+ years, these probes are still less than 1 light day away from home. A light year is vast.
NKosmatos 4y ago
Whenever I read something related to the two Voyager probes I feel a little bit sad about them since they’re out there on their own. At the same time I feel pride for humanity as a species, since we managed to send these two probes so far away.
- SirAllCaps 4y ago
  Getting the probe out there is no doubt indeed remarkable in its own right, but to build it resilient enough to remain communicative at this distance, after all this time in such hostile environment, along with the foresight that enables these lifetime measures to be taken almost a half century later, makes it all more remarkable, and to think all this accrued knowledge and ingenuity being generalized from things like chipping flint axes.

217 points by taubek 4y ago

e12e 4y ago

Does anyone know if JPL have "local copies" of Voyager 1 and 2 that they can test things like this hack on? Or do they just plan it out and try on the probes themselves?

hi 4y ago

JPL Press Release: https://www.jpl.nasa.gov/news/nasas-voyager-will-do-more-science-with-new-power-strategy https://www.jpl.nasa.gov/news/nasas-voyager-will-do-more-sci...

bruce511 4y ago

Everything about Voyager is just mind-blowing. These are 45 year old electronic devices, using 70's tech, with zero maintenance, operating 22 light hours away. At that range they can still send messages detectable on earth. 9 out of 10 instruments are still working. People just leaving school when they launched are already retired. This is one time when the adage "they don't make them like they used to" is well applied. Hat tip to all involved.

hulitu 4y ago
> Everything about Voyager is just mind-blowing. These are 45 year old electronic devices, using 70's tech, with zero maintenance, operating 22 light hours away. No, what is mind blowing is that we are not able to do it again.
- jfengel 4y ago
  We did do it again. We got New Horizons out to Pluto a lot faster, without the aid of the remarkable alignment that made Voyager possible. We keep exploring the solar system. There's no reason to repeat the same experiments. We've explored the planets in a lot more depth, and just launched even more.
derrasterpunkt 4y ago
Voyager 2 had 11 instruments. 5 are still active. But still, it is a remarkable piece of technology.
schmichael 4y ago
Agreed, but I believe Voyager is 18.5 light hours away, not 22. The article says it is 20 billion km away which is 18.5 light hours. However the article also states signals take 22 hours to reach the spacecraft. Do radio waves travel slower than the speed of light even in the vacuum of space? I assume the waves do not spend the extra 3.5 hours in Earth's atmosphere!
- ars 4y ago
  The article is rounding up, and the parent comment is talking about Voyager 1. Specifically: Voyager 1 is 23.8 billion km (23.8 Tm), and Voyager 2 is 18.3 Tm.
  - dylan604 4y ago
    For those that might not be aware, Voyager 2 launched before Voyager 1, so the distance discrepancy is not due to the further one being launched first
    - bragr 4y ago
      Voyager 2 was launched first but on a less direct trajectory out of the system which allowed it to visit Uranus and Neptune. Voyager 1 is going much faster https://voyager.jpl.nasa.gov/mission/status/ https://voyager.jpl.nasa.gov/mission/status/
- urubu 4y ago
  There is an effect called dispersion, which causes different frequencies of electromagnetic radiation to travel through a medium at different speeds (lower frequencies => slower). It's strong enough to be noticeable in the case of pulsars (but probably insignificant inside the solar system).
- sosodev 4y ago
  I think it's because space isn't a perfect vacuum. The interstellar medium is a mix of gas and dust that slow down and weaken the signal. That effect is known as dispersion. With that said, it seems like the article might be inaccurate. That discrepancy seems too large to be explained by dispersion. I'm not an expert though. edit: I think the author got Voyager 1's distance mixed up with Voyager 2. Voyager 1 is ~22 (21.6) light hours away.
shagie 4y ago
Btw, you can see the occasional communication with Voyager at https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html As I write this, one of the dishes at Madrid just went to "Setup" for communication with VGR1. (late edit - some of the stats from the 'more info' at the bottom of the spacecraft panel) DATA RATE 160.0 b/sec POWER RECEIVED -160 dBm (1.0 x 10-22 kW)
enkid 4y ago
I mean, with a few notable exceptions, NASA's scientific missions have an amazing record of lasting much longer than they were designed for, Hubble and the Mars rovers & helicopter being amazing feats of lasting longer then they should.

croutonwagon 4y ago

Heres another article I read today that had some specifics. They are disabling a voltage regulator to save power and prioritize the science instruments as a calculated risk. https://phys.org/news/2023-04-nasa-voyager-science-power-strategy.html https://phys.org/news/2023-04-nasa-voyager-science-power-str... >In search of a way to avoid shutting down a Voyager 2 science instrument, the team took a closer look at a safety mechanism designed to protect the instruments in case the spacecraft's voltage—the flow of electricity—changes significantly. Because a fluctuation in voltage could damage the instruments, Voyager is equipped with a voltage regulator that triggers a backup circuit in such an event. The circuit can access a small amount of power from the RTG that's set aside for this purpose. Instead of reserving that power, the mission will now be using it to keep the science instruments operating. >Although the spacecraft's voltage will not be tightly regulated as a result, even after more than 45 years in flight, the electrical systems on both probes remain relatively stable, minimizing the need for a safety net. The engineering team is also able to monitor the voltage and respond if it fluctuates too much. If the new approach works well for Voyager 2, the team may implement it on Voyager 1 as well.

jacquesm 4y ago

If there is on thing this demonstrates then it is that the combination of good documentation and clever engineering can go a long, long way.

evan_ 4y ago

I'm amazed that they're able to disable a voltage regulator remotely. Did they just build in relays for every single component in case they wanted to rewire everything on the fly or was this something they specifically knew they might want to do 45 years ago?

sgtnoodle 4y ago
Yeah, I'd say it's actually pretty common to make spacecraft avionics as remotely switchable as possible. For one thing, there's likely to be a considerable amount of redundancy so that a single component failure doesn't ruin your whole mission. It's good practice to have a way to isolate any component that is anticipated to fail. FDIR is a known acronym: fault detection, isolation and recovery.
CodeWriter23 4y ago
They probably implemented fail-safe relays with circuitry to disengage automatically under hazardous conditions but also controlled remotely.
foobarian 4y ago
Also I assume there isn't a web service running there with a "enable/disable" endpoint to control stuff. Wonder what the control stack looks like. Turned up this from https://voyager.gsfc.nasa.gov/Library/DeepCommo_Chapter3--141029.pdf https://voyager.gsfc.nasa.gov/Library/DeepCommo_Chapter3--14...: > The signal consists of 16-bps, Manchesterencoded commands, biphase modulated onto a squarewave subcarrier frequency of 512 hertz (Hz). There are references to fuller descriptions of the command set but I haven't found them yet.
- stouset 4y ago
  I can't help but wonder how possible it would be (or would have been at some point in the past) for a person with evil intent to send unauthorized commands to these probes. How are signals authenticated? At this point, is it just that there are only a handful of parties capable of sending a strong enough radio signal to a precise-enough location in space, and who know the position of these probes to the degree of accuracy required?

itslennysfault 4y ago

Ya know...... Considering how long it takes these things to get to deep space we probably should've kept the Voyager program going. By that, I mean we should've continued iterating and launching Voyager probes. If we launched one every 2 or even 5 years we'd have between 22 and 9 additional probes heading into deep space a couple years apart. Each with slightly better tech than the previous.

kristianp 4y ago
Agreed. Every time I see a story about the Voyagers, I wonder why a follow-up hasn't been done that is much faster and more capable.
- thatcherc 4y ago
  It's the same reason the Voyagers launched in the late 70s - the Grand Tour configuration of the planets [0]. The outer planets align in a way that lets you chain together several gravity assists to achieve high enough speeds to escape the solar system. The trick is that configuration only occurs every 175 years. I don't think we have any space vehicles right now that could produce that same kind of delta-v with their own chemical/electrical/nuclear power. [0] - https://en.wikipedia.org/wiki/Grand_Tour_program https://en.wikipedia.org/wiki/Grand_Tour_program
  - skykooler 4y ago
    It's feasible to do an alternate route to the outer solar system by using an ion engine, dropping the perihelion down below Venus's orbit and then using a Venus -> Earth gravity assist chain with the ion engine going the whole time. The downside is that this is a more lengthy process than the Grand Tour route, and you have to do all your maneuvers in the inner solar system because ion engines draw a lot of electrical power and solar panels get very weak once you get past Mars or so.
- CamperBob2 4y ago
  Probably because it made more sense to use the general information obtained from the Voyagers to design probes with specific capabilities to explore specific planets. The Cassini/Huygens mission might be a possible example.

FridayoLeary 4y ago

The probes get their power from the decay of a plutonium isotope. The question is why can't we find applications for this technology on earth, for example to power your house or something?

allisvancity 4y ago
They evidently used to use radiothermal generators (RTGs) as the power source for some pacemakers. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#History https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge... Plutonium is nasty & expensive stuff, however. That puts some pretty severe limitations on its usefulness for domestic purposes.
- 1letterunixname 4y ago
  RTGs in humans: not for a long time.
deleted 4y ago
[deleted]
neaden 4y ago
It's a very small, but stable, amount of power generated given the amount of plutonium and the costs/risks of it it's not really worth it for anything else. Geothermal for instance for a home would make much much sense.
speed_spread 4y ago
The USSR did that for a while. It didn't end well for some people. https://en.m.wikipedia.org/wiki/Lia_radiological_accident https://en.m.wikipedia.org/wiki/Lia_radiological_accident
- FridayoLeary 4y ago
  Thanks for that source. Maybe it's impractical for domestic use but it looks like they found uses for it in isolated locations for industrial purposes. Obviously it needs to be handled responsibly.

7373737373 4y ago

Video recommendation: How To Contact The Voyager 2 Probe (https://www.youtube.com/watch?v=FzRP1qdwPKw https://www.youtube.com/watch?v=FzRP1qdwPKw) and Pinging The Voyager 2 Probe (https://www.youtube.com/watch?v=1rCrfQUcXDI https://www.youtube.com/watch?v=1rCrfQUcXDI) by EEVDiscover

noodlesUK 4y ago
Thank you so much for these links. These are much more detailed videos than I expected going over the RF and antennas involved.
1letterunixname 4y ago
Dave! :D
- cwillu 4y ago
  Don't turn it on, take it apart!
  - 1letterunixname 4y ago
    Correction: apaaat

sammyjoe72 4y ago

What blows my mind is that even after 40+ years, these probes are still less than 1 light day away from home. A light year is vast.

NKosmatos 4y ago

Whenever I read something related to the two Voyager probes I feel a little bit sad about them since they’re out there on their own. At the same time I feel pride for humanity as a species, since we managed to send these two probes so far away.

SirAllCaps 4y ago
Getting the probe out there is no doubt indeed remarkable in its own right, but to build it resilient enough to remain communicative at this distance, after all this time in such hostile environment, along with the foresight that enables these lifetime measures to be taken almost a half century later, makes it all more remarkable, and to think all this accrued knowledge and ingenuity being generalized from things like chipping flint axes.