
The Brains of the Voyager Spacecraft: Command, Data, and Attitude Control (2017) - dddddaviddddd
https://www.allaboutcircuits.com/news/voyager-mission-anniversary-computers-command-data-attitude-control/
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walrus01
> "The Voyager FDS would be the first spaceflight computer to use CMOS
> volatile memory. This was a big step since it was a fairly new technology
> and, if power was lost to the ICs for a moment, all memory would be lost,
> too. However, a direct line from the radioisotope generators, which provided
> direct current, was used to ensure the CMOS ICs would never lose power
> unless something happened to the generators. It was decided that, if
> something had happened to the generators that rendered them inoperable,
> there would unlikely be a need for the FDS, anyway."

Sort of like having a PCI-Express bus RAM drive card full of DDR4 DIMMs, in a
computer that'll never be powered off, because it has the most ridiculously
protected N+1 power supply and UPS system imaginable.

Since there's a single RTG per craft, and failure of the RTG would very
quickly kill the entire craft due to lack of power and extremely cold
temperatures, seems totally logical.

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sandworm101
One day the voyagers will be gone from our perception. I'm not happy about
that. We need something else chasing them into the dark. We should send
another. It doesn't need to be a massively complex craft. Slap a big antenna
and some RTGs onto a satellite bus. Then an ion engine as a slow boost stage
and launch the package. Do a lap or two between earth and mars to build up
speed, then aim for Jupiter. Science is great, but having that candle out
there should be reason enough.

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nine_k
I wonder if the technology has advanced enough to make this feasible for a
(large enough) private org. Maybe not exactly for a kickstarter campaign, but
for a group of wealthy sponsors who would donate several dozen millions each.

The cost of the space launch went down dramatically. Many components are
standardized and thus less expensive. CAD systems allow a much smaller number
of engineers to design the custom parts. New materials, like maybe carbon
fiber, could help make the thing lighter weight. Computing the orbital
mechanics with great precision is within capabilities of a laptop.

This seems to be just on the brink.of achievable.

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dylan604
Has anyone reached to S R Hadden to see if he's willing to chip in? I think
sending a satellite in the direction of Vega might be of his interest.

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joezydeco
Yeah he died a few months ago but nobody is supposed to know about that yet.

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keyle
It's incredible, today we can't keep a bunch of apps running in virtualized
containers in virtual machines in some data centre across the world... But
these two little things are still chugging along on the outskirts of our solar
system in the harsh conditions of space.

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aloknnikhil
I don't get such comparisons. The voyager had a single purpose - to travel
through space. It was purpose built for that and that alone. Things were
simple. Definitely an engineering marvel for that time. Between now and then,
we've had reusable rockets, multiple landers, developing nations launch
rockets at a tiny cost of the original project. Things have improved. Let's
compare that.

Data-centers serve billions of people and have significantly more challenges
in maintaining SLAs. It's not a trivial problem to solve.

~~~
eru
They serve billions of people and serve them cheaply!

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hliyan
I was actually more impressed by one of the references of the article than the
article itself:
[https://history.nasa.gov/computers/Ch6-2.html](https://history.nasa.gov/computers/Ch6-2.html)

Did not know history.nasa.gov existed...

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dddddaviddddd
I read this after seeing this submission earlier today:
[https://news.ycombinator.com/item?id=21285793](https://news.ycombinator.com/item?id=21285793)

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ngcc_hk
Luckily it was v1/2.

Not v6 that leads to Star Trek the first movie. Lost the memory might lose the
mission - to collect all info and return to the creator.

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mitchtbaum
any friend who keeps in touch no matter how far away they get is a friend
worth keeping

[https://en.wikipedia.org/wiki/Radio_drama](https://en.wikipedia.org/wiki/Radio_drama)

