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Bunch of napkin math: you'd need something like 10 kilowatts and 140 km/s detla-v to catch up to Voyager in a decade, assuming a New Horizons equivalent Earth escape velocity. The amount of xenon is technically possible, however even assuming impressive 8000 Isp thrusters, your fuel mass fraction ends up being 90+% fuel which doesn't leave a lot of mass for that reactor and radiators.

A 20 year intercept would be pretty reasonable though. It needs about 15 km/s delta v after that NH style escape, about a kilowatt of power, and maybe a 25% fuel mass fraction at 6000 Isp. That's all very reasonable by current standards.


Is that including a Jupiter/Saturn assist?

No, that's more than napkin math but I feel the numbers stand for themselves that we can't really do better than decades. A few km/s won't change that.

I understand that celestial mechanics are involved, because "stuff in space do not fly on straight lines", but why is the delta V budget 10x smaller for 2x more time? That feels counterintuitive :/

The dearth of case law here still makes a negative outcome for FSF pretty dangerous, even if they don't appeal it and set precedent in higher courts. It might not be binding but every subsequent case will be able to site it, potentially even in other common law countries that lack case law on the topic.

And then there is the chilling effect. If FSF can't enforce their license, who is going to sue to overturn the precedent? Large companies, publishers, and governments have mostly all done deals with the devil now. Joe Blow random developer is going to get a strip mall lawyer and overturn this? Seems unlikely


The restrictions on GPS prevent ballistic missiles, not MANPADs. Typical limits are 515 m/s and 18,000 meters (try using your phone's GPS on a commercial flight, it works fine near a window). Update rate is probably the biggest issue with GPS and MANPADs.


Are these chips so much better at calculating GPS position than general purpose CPUs or consumer FPGAs? Feels like a silly restrictions for anyone capable of building a ballistic missile. On the other hand it seems relatively computationally expensive to do a speed check every time for low energy devices.


The headline is a bit sensational considering all we know from the reporting is that he isn't working there anymore. Fired likely, sure, but not for a fact.


My phone can regularly pick these up with a clear western view in Los Angeles. They're relatively low in the sky so they don't serve their intended purpose here, but I'm not complaining about having more satellites to lock on to.


Western view?


A view of the sky to the west


Large fleet operators tend to self insure rather than having traditional auto insurance for what it's worth.

If you have a large fleet, say getting in 5-10 accidents a year, you can't buy a policy that's going to consistently pay out more than the premium, at least not one that the insurance company will be willing to renew. So economically it makes sense to set that money aside and pay out directly, perhaps covering disastrous losses with some kind of policy.


It sounds like they want flexibility for immigrants who may feel the need to keep a low profile, despite their legal status.


Looking at prices, I think you are wrong and automotive Lidar is still in the 4 to 5 figure range. HESAI might ship Lidar units that cheap, but automotive grade still seems quite expensive: https://www.cratustech.com/shop/lidar/


Those are single unit prices. The AT128 for instance, which is listed at $6250 there and widely used by several Chinese car companies was around $900 per unit in high volume and over time they lowered that to around $400.

The next generation of that, the ATX, is the one they have said would be half that cost. According to regulator filings in China BYD will be using this on entry level $10k cars.

Hesai got the price down for their new generation by several optimizations. They are using their own designs for lasers, receivers, and driver chips which reduced component counts and material costs. They have stepped up production to 1.5 million units a year giving them mass production efficiencies.


That model only has a 120 degree field of view so you'd need 3-4 of them per car (plus others for blind spots, they sell units for that too). That puts the total system cost in the low thousands, not the 200 to 400 stated by GP. I'm not saying it hasn't gotten cheaper or won't keep getting cheaper, it just doesn't seem that cheap yet.


>it's hidden behind a couple of touch screen actions involving small virtual buttons and it does not pull over immediately

It was on the home screen when I've taken it, and when I tested it, it seemed to pull to the first safe place. I don't trust the general pubic with a stop button.


No? Almost every big defense contractor is publicly traded.


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