Yes this is also a question that comes to my mind. Where are the design docs from the past 50 years of software development. There must be something concrete for people to study and learn from.
I've been doing this stuff for 40 years and spent the first 20 or so looking for design documents (having been asked to write many). Eventually I realized there are none. At least almost none, and very few that existed prior to the related software being written.
Hmm it's just a turn of phrase. I would bet you $100 that no more than 0.001% of the population have heard of BPS. I hadn't. That's functionally "nobody".
The title is still clickbait given the reason nobody has heard of it is that it barely exists and is not useful yet.
Also, it smelled a bit like wishful thinking to assume the high precision clock would not be driven by GPS on real world deployments. I know some cell towers synchronize via PTP, but a great many others use GPS as their time source.
For anyone who deploys GPS-based timing systems at scale, having more sources of precise time is a huge boon. (Some companies pay many millions for dark fiber just to have a redundant time source).
Holdover can only help so much, if there's a persistent jamming effort, it can wreak havoc on many time-critical systems.
India possibly. It's not much in the geopolitical discussion, but in 50 years time, may be earlier, India will have a larger economy than the US. That will truly be then end of the "American Age". Whole playbook which has been applied to USSR, China won't apply either.
Even as on today, moving to India and Indonesia and similar countries will bring similar quality of life that people get in the US at a lower cost. Rents, Healthcare, labour all are much cheaper. Interest rates are much higher.
You'll even get things like quick-commerce, which isn't really taking-off in the US.
The transcript of the video doesn't really work that well as the intro text in GitHub. The tone of it feels haughty, before even it has entered into the main details of the project. My suggestion is to rewrite it toning down the things that work on video but not as standalone text.
For what it’s worth, I didn’t find it “haughty” or tonally inappropriate at all (I thought it was fun and cute, and the right kind of unserious tone for a hacking-for-fun project).
If we’re doing a line-level read, though, it did take me a lot of reading to understand what the project was. Nothing that couldn’t be addressed with one more massage of your subhead “a physical chess board without the concept of turns”!
Super cool project, incredible execution, and you’re so personable—thank you for this work and your video!
Naturally. I've rented an mini excavator in the past to dig up stumps for a one time job. It made sense more sense to rent it since it was for a one-time task, and purchasing the kubota would have cost more than 5k.
Given we're on HN news, I thought it was implied that I was referring mostly to the exhaustion at being faced with a perpetually increasing amount of rent-seeking in the form of SaaS.
Additionally, for a lot of professional software, we aren't given the option for short term rental. For creative cloud, I pay monthly but agree on a annual basis. There's a more expensive month-to-month sub, but still you have it at minimum for a whole month.
With software subscriptions, I don't have the option of saying "I need to rent lightroom for 3 hours to edit this session." and have it be priced accordingly. No matter what, I'm on the hook for at minimum a month. On the flip side of that, since I use it so frequently, it's insulting that my only option is just to rent it. I can buy other tools outright and own them, so I'd also like to own my digital tools as well.
Fear of Chernobyl catastrophe was the major reason to demand free speech. Free speech made it clear that USSR is far behind western countries, it opposes. Which created demand to catchup with West or/and to dismantle inefficient soviet regime (AKA «Go West»[1] or «Light from the West»).
Its actually sometimes more than 40% and that's not even for luxury cars.
Here's[1] an example for a car costing a million INR, taxes are more than 300K. That's not the final landing price. Final price adds up extra road tax component that is anywhere from 13 to 17%(or even more) which is calculated on top of the 1 Million.
In case you missed it, that's tax on tax i.e. double taxation! Some courts have ruled it illegal but majority of state governments act ignorant and just continue the practice.
JPL and whoever's behind engineering for the ESA have decades of experience on the Indian space program.
I believe the approach is to shut down all nonessentials and run a heater to keep the battery above failure level during the night. This sounds simple but I'm pretty sure it's an absolute nightmare to design autonomous systems for, especially when you've only encountered those situations theoretically or in a controlled lab environment.
Space is hard. It hates us. It hates life. It hates any form of order and will actively attempt to destroy it. Trying to make things that survive in space is Difficult. It would have been easy to go "Lol india amirite", but the fact is, this is one of the hardest things humanity can do.
Especially for someone who never experienced anything lower than -5°C. Most cars wouldn't even start at -20°C if not equipped with a more powerful generator and battery from the factory. This is measly 20° difference.
I made the mistake of going splitboarding in the backcountry a few years back in -20°C with -40°C windchill.
Going up the mountain was surprisingly fine. I even had taken off both my jackets and was just wearing thermals as the heat I was generating working to go uphill was enough to keep me comfortable.
Unfortunately when we reached the top, we also ended up directly in the wind with no available cover. Within the ten minutes it took to put my jackets back on and transition to go downhill, I was nearly hypothermic. I couldn’t even operate my fingers enough to bring the idiot-proof magnetic clasp on my helmet together. The whole group was on the verge of panic to get off the top of that ridge. If we’d stayed there five more minutes, I’m not confident we would have made it back home that day.
I can’t fully express how obscenely, unconscionably, and incomparably cold that was. I have never felt anything like it and I hope never to again.
I once encountered -30°F one winter in Fairbanks. I visited a hot spring where, for some cruel and unusual reason, the facility was designed so you needed to walk about 10 meters out of the (well heated) building to get to the water. And of course, you would do this walk in nothing but just your bathing suit. That was the longest 10m walk of my life.
The cherry on the cake of the experience was that you get into water that is 70+°F but every part of your body above the water line is exposed to -30°F winds. Fun!
Where I grew up, each winter there were a few days that started at -30-40°C.
Walking is not too bad (in the squeaky snow) because usually there's NO wind. Cars usually had (plug-in engine-coolant) 'tank heaters' and battery trickle-chargers to keep engines startable.
But there were plenty of snowmobile riders in the area. Some of them who bundled up and attempted to ride at these temperatures learned that their lungs did not work well after a short time.
Living in Ulaanbaatar Mongolia for some time I experienced temperatures of -20 -30 -40 Celsius. Every ten degrees lower I thought it was going to be the same, but was I wrong.
My most notable discovery was when I wanted to jump start my car, because the battery died due to the cold. I was about to bring out my jumper cables when my local friend told me to bring the cables inside first.
I didn't understand why and naively ignored what he said only for the rubber jumper cables to literally crumble in my hand, breaking as I tried to straighten them.
Mongolians are so resilient and have so much knowledge on how to survive in extreme weathers with a simple yurt and a livestock of 100 sheep goats and horses.
Most modern cars will happily start at -20°C and many will start at -30°C without any special additions (don't ask me how I know, you just need to know what you are doing). Of course it's not -200°C, but one thing to remember is that there is no temperature in the vacuum. The temperature of the Lunar surface is not it. An object without heating can easily reach lower temperatures there, yet it may not be that hard to keep that object warm as e.g. somewhere in the Arctic as there is no conductivity, only the radiation heat transfer.
> Most modern cars will happily start at -20°C and many will start at -30°C without any special additions
A couple years ago temps here went below -25° and there were a lot of cars which didn't go nowhere. Sure, some of them just had a battery too low from the usual urban minimal distance travel, but I heard enough rants from and about people who was forced to abandon their car and use the public transport or taxi. Diesels without an engine heater were among them.
> don't ask me how I know, you just need to know what you are doing
Ye, have an 'offline' (lol) charger for your car battery or have a 'kick-starter' kit. The thing is what the cars sold here are prepared for the winter conditions, yet many of them failed at a slightly lower temps - which again shows how a mere 5° difference can be way too much even for things what work otherwise just fine.
People just don't care about their vehicles, that's why. There are multiple examples of even diesels starting at -25°C without heating. All my cars have been gas and while starting them at -30°C required some magical actions (like turning on headlights briefly to warm the battery up or depressing the clutch if you have a manual transmission) they all started most of the time. No extra tools or devices were necessary.
> or depressing the clutch if you have a manual transmission
What exactly does depressing the clutch do as compared to not doing it and starting the vehicle in neutral? Is it to reduce the engine load further? Or something else?
Standard gear box oil is 80W90, which at -30C (even at -20C) turns into a thick jelly. Even in neutral starter has to move gears in that jelly. So normally you don't want to release the clutch until engine is warm enough and stable, and even when you do release it (in neutral) you do it slowly, sometimes in multiple attempts to avoid engine stalling, like starting on a steep hill. I haven't tried automatic at those temperatures, but ATF is much less viscous, so it should be much easier on the starter at low RPM.
It got below 0F a couple years ago and my garage door wouldn't open.
-200C in a vacuum is an entirely-different engineering paradigm as I understand it. Materials just don't behave the way we expect at regular temp/pressure.
There was a whole writeup (on here, IIRC) about the engineering behind the only (or one of less than a handful) types of planes that can transit Antarctica during the cold, dark months.
The fuel freezes, the oil freezes, the rubber in the tires and gaskets becomes brittle, and basically nothing normal works. I recall it being similar-but-different to the SR71 modifications, where the parts are loose and continuously leaks fluids because the materials all change shapes so much in the environment they're designed for. And of course it all has to return to the initial state for (a safe) landing.
Stupid question, and maybe I should have web searched for it, but why did the fuselage expend? Something to do with the heat generated by the high speed and hence by the high friction?
> It hates any form of order and will actively attempt to destroy it.
If you are talking about ever increasing entropy, it applies to any environment. But keep in mind that the Moon itself is a manifestation of order. If it hadn't been the case we would have been observing a cloud of dust and gas where our Solar system is.
Yes, entropy increases in the salad dressing, but only when it's insulated (in reality we can't consider salad dressing outside of the Earth gravitational field, but let's say the Earth is insulated too). Now imagine that the extra energy (i.e. generated heat) has dissipated (either out of a window or, if we consider the Earth too, into the space). Is it still an increase of entropy? Our Solar system is not a closed system, the extra heat that was generated by creation of planets has dissipated (and is continuing to do so). So in the end the entropy of the Solar system is lower, i.e. we have more order, at least in our vicinity. Possibly in the whole universe since it's (presumably) expanding. Anyway, I wouldn't apply 2nd law of thermodynamics to the whole universe, we have no idea what happens at that scale.
1. Design goals. The program had a budget, and with that budget their goal was a 14 day target. Anything extra is icing on the cake. They could have used an RTG to ensure long term survival, but it would have exploded their budget.
2. If I remember correctly the probe is in the south pole of the moon. Most probes are closer to the equator. The poles get colder and I think in some circumstances have more night time
3. Experience. This is their first successful moon probe. Now they understand the parameters better, so maybe next one will do better?
By having some source of heat, for example, while the Chinese rover from a few years ago was solar powered, it had a radioisotope heater which used the heat produced by some plutonium-238 to keep the electronics warm enough to survive the night.
They use RTGs[1] as the power and heat source, I think CY3 was just solar powered and did not have thermal protection you get from RTGs for electronics.
That's a very big stretch of your imagination as its a legitimate argument and discussion to be had. Perhaps not amongst ultra Indian nationalist for which HN has many and your comment makes me feel you may be catering towards.
OK, but your low-information comment was predictably provocative.
That makes it flamebait, as well as breaking this guideline: "Comments should get more thoughtful and substantive, not less, as a topic gets more divisive." - https://news.ycombinator.com/newsguidelines.html
Glib comments on top of long and torturous histories regularly set opposing commenters off. Even if the vast majority of readers aren't provoked, there's enough area under the long tail to guarantee it. The responsibility is on you not to post something with that expected value (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...).
I respect HN for it's high commentary and why I avoid places like Reddit where possible. I admit, I should have made the comment of higher quality and provided sources, I was attempting to initiate discussion about the topic.
@dang, please check my comment history. I am not a "nationalist", but I am tired of comments like these which continuously seem to appear in HN. Every. Single. Thread. about anything India does, and these people come out of the woodwork: "but people are still shitting in the streets! but there is no drinking water! Snake charmers hurr durr!"
I'm sorry, but you were both at fault. The other commenter posted a flamebait provocation and you took the bait and responded by breaking the site guidelines even worse. This is how internet forums destroy themselves, so we really need to be proactive about not doing this.
Of course I also hear your underlying point and understand your frustration. I don't doubt that it's legitimate. But legitimate frustration doesn't make it ok to break the rules like that; on the contrary—legitimate frustrations are common enough, on such a wide range of topics, that this would make the whole site a big flamewar.
