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NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

science.nasa.gov

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Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#61

Post by monocasa »

bombcar wrote: post #35
anigbrowl wrote: post #31

It continues to irritate me that There aren't any other functioning deep space probes besides New Horizons (launched in 2006, and which flies at a slower speed than Voyagers). One new operating deep space probe in nearly 50 years is just embarrassing. I mean yay space telescopes and everything, but we seem to have given up anything that isn't a state-of-the-art prestige project. I was hopeful about projects like Brea…

Isn't a big part of the problem that the voyager slingshot is one of the best you can get, and it's a once in multiple-lifetimes event? Even if we launch a new deep space probe as best we can they're gonna be real slow?

For Voyager 1, Jupiter's gravity assist was the only one that increased velocity, the flybys ultimately sapped velocity.

Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#62

Post by Evidlo »

peteforde wrote: post #58

I would love to better understand how a device launched the year before I was born could be so flexible in its configuration and operation. I can't update the code running on a microcontroller on my desk in front of me without it triggering a reboot. When they talk about rerouting power and performing a "big bang" reconfiguration with a 23 hour lag on equipment that was underpowered when the 8088 came out... it kind…

> microcontroller on my desk in front of me without it triggering a reboot

Most microcontrollers can update their own flash while running, either with a built-in bootloader or a user-programmed bootloader that takes up a little bit of the flash.

What makes you think that Voyager isn't "rebooted" though?

Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#63

Post by tavavex »

peteforde wrote: post #58

I would love to better understand how a device launched the year before I was born could be so flexible in its configuration and operation. I can't update the code running on a microcontroller on my desk in front of me without it triggering a reboot. When they talk about rerouting power and performing a "big bang" reconfiguration with a 23 hour lag on equipment that was underpowered when the 8088 came out... it kind…

NASA pioneered a lot of what underpins modern design of critical computer systems. Voyager's systems are impressively robust. As far as I know, they can patch it by directly sending up new assembly instructions that are written into its memory, and doing a warm reboot to get it to start executing new instructions without powering down anything. They had the foresight to make their software highly editable, while also having multiple redundancy and emergency systems. Despite this, I wonder how much pressure the people writing this software feel. Even with all the simulators and months of rigorous testing, sending up something that can (in the worst case) break the probe has to be terrifying.

Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#65

Post by sudo_cowsay »

tavavex wrote: post #64

Is there an exhaustive list of all the systems and experiments that are still running on these probes? I'm really curious about what data it's collecting and sending back to us.

here: https://science.nasa.gov/mission/voyager/instruments/

Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#66

Post by tavavex »

sudo_cowsay wrote: post #65
tavavex wrote: post #64

Is there an exhaustive list of all the systems and experiments that are still running on these probes? I'm really curious about what data it's collecting and sending back to us.

here: https://science.nasa.gov/mission/voyager/instruments/

Thanks! Looks like it's just the magnetometer and a receiver instrument. Once the pool of instruments runs dry, I wonder how thinly they'll be able to slice the functionality of the remaining, non-experimental systems to prolong their lifetime as much as possible.

Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#68

Post by mmooss »

dylan604 wrote: post #37
anigbrowl wrote: post #31

It continues to irritate me that There aren't any other functioning deep space probes besides New Horizons (launched in 2006, and which flies at a slower speed than Voyagers). One new operating deep space probe in nearly 50 years is just embarrassing. I mean yay space telescopes and everything, but we seem to have given up anything that isn't a state-of-the-art prestige project. I was hopeful about projects like Brea…

What else are you looking to see from such deep space? Nothing we launch will ever reach anything anything interesting in probably the life of humanity. Just to get to Pluto in our life times meant going so fast that it could only fly by. Maybe flying around in the Oort cloud might, unlikely though, be interesting.

> What else are you looking to see from such deep space?

Deep space itself - that's what the Voyagers are measuring.

Re: NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

#69

Post by mananaysiempre »

Evidlo wrote: post #62
peteforde wrote: post #58

I would love to better understand how a device launched the year before I was born could be so flexible in its configuration and operation. I can't update the code running on a microcontroller on my desk in front of me without it triggering a reboot. When they talk about rerouting power and performing a "big bang" reconfiguration with a 23 hour lag on equipment that was underpowered when the 8088 came out... it kind…

> microcontroller on my desk in front of me without it triggering a reboot Most microcontrollers can update their own flash while running, either with a built-in bootloader or a user-programmed bootloader that takes up a little bit of the flash. What makes you think that Voyager isn't "rebooted" though?

This kind of update is often kind of ass to do, though, because you may not be able to execute from said flash while you’re updating it.

So you copy a small write routine into RAM, copy a chunk of new data there too, jump to the routine, then it returns to your main bootloader in flash which receives the next chunk from a UART or whatever (because of course it doesn’t fit into RAM all at once), rinse and repeat. You aren’t exactly going to be serving realtime interrupts during this.

(So if you do need minimal downtime, you probably have dual external flash chips, or even just two microcontrollers given execute-from-external-flash would bump you up to fancy micros.)

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