The thruster fix is the part that gets me. They sent a command that would either revive thrusters dead since 2004 or cause a catastrophic explosion, then waited 46 hours for the round trip with zero ability to intervene. That's a production deployment with no rollback, no monitoring dashboard, and a 23-hour latency on your logs. They nailed it.
I'd argue that once you have a very well defined requirement doc that mostly kicks humans out of the picture, as well as a patient boss who doesn't want anything ASAP or "Tomorrow morning first thing", engineering is not that hard, and is almost...enjoyment.
> ASAP or "Tomorrow morning first thing"
like in "fast pacing environments" with "flat hierarchies" and "agile mindset"? :-D
As ASAP As Possible
As asap as possible or you can say rip in peace to yourself
A well defined doc evolves over time. it gets sharper with real-world scenarios, incidents, and experiments. Before Voyager 1, we didn’t have that kind of experience. You can’t predict everything upfront.
> Theory only takes you so far
I’d argue that you must not be working on interesting problems if you think that “engineering is not that hard”
I think their point is that the challenge becomes more enjoyable than tedious.
That's the point. I haven't but I would like to, and I realize that the so called "engineering" problems I work on is NOT real engineering.
OK I was probably wrong about that "not hard" though.
Would sending voyager have been a real definite deadline?
Visiting this many planets was only possible due to a very rare alignment. It's a once a century event. That's why we sent two probes, not just one
Absolutely. You could wait decades or centuries for a useful planetary alignment.
Not really. Jupiter alone is good enough. Its huge mass accounts for almost all of the gain you get from any such slingshot. Launch windows from Jupiter to anywhere occur every 12 years. Voyager's alignment was captivating, but realistically if it hadn't happened, we would have just done separate Jupiter-Uranus and Jupiter-Neptune missions instead.
Based on the communication fix, they also didn't have a simulator, or tests, or complete source code, on a custom instruction set that wasn't well documented, so they had to reverse engineer how it worked. https://www.youtube.com/watch?v=YcUycQoz0zg&t=2366s
That was ballsy! But, sadly, it was a temporary hack. Both Voyager have degrading, unfixable thrusters. The rubber diaphragms in the hydrazine fuel tanks are degrading, shedding silicon dioxide (i.e. sand) microparticles into the thruster fuel. These particles are gradually clogging the thruster nozzles and reducing their thrust. Eventually, thrust will decline to the point that they could fire the thrusters all day long and still not impart enough momentum to point the probes at Earth. Once that happens, we'll lose contact with the probes.
They'd switched away from the primary thrusters in 2004 due to this degradation. Now the backups are so degraded that the primary thrusters are better again in comparison.
Thruster clogging will kill Voyagers in about five years if nothing else gets them first. The least degraded thrusters nozzles are down to 2% of their diameter --- 0.035mm of free-flow area remaining.
The Voyagers will probably celebrate their 50th anniversary, but not much beyond that. :-(
Kind of ignominious to be done in not by the inexorable decline of radioactivity but by an everyday materials science error of the sort we make on earth all the time. In the 1970s, we knew how to make hydrazine-compatible rubber. We just didn't use it for the Voyagers.