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stevep98

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Global cellular operator revenue is approx $1T. They have put their toe in the water with direct-to-cellular support for starlink, and have bought spectrum to improve this. I'm sure they basically want to offer cellular to everyone in the world and get a good chunk of that $1T. Maybe they want 20% of it? Sounds crazy, but China Mobile, Verizon, and Deutsche Telecom each have 10%. Sounds it's not so wild that they can grab a big chunk, especially if they can find new customers that are not already connected.

And of course they can also continue to grow their broadband internet access business.

I suppose they will likely start putting cameras and other data sensors on the satellites so they can sell other data for mapping, positioning services, agriculture, weather, etc. The incremental cost to add this to the platform will be almost nothing compared to existing systems.

Once in a while I get inspired by a post on HN, but I know I don't have the energy to follow it through. Here's my idea for anyone who thinks they can do something with it:

Imagine you are holding in your hand a small glassy sphere. Initially it looks like random dots inside, but as you play with it in your hands, you get glimpses of images of loved ones.

To implement this, select a bunch of photos of people, generate pseudo-3d models of their faces with your AI of choice. Position them around a sphere in a 3D modelling software, and generate a whole bunch of renderings all around the scene. Now, feed those renderings into gaussian splat software.

The resulting 3D gaussian splat should include relatively high fidelity when the viewer is aligned with the supplied iamges, but more stochastic nonsense when misaligned. This should contribute to the feeling of being able to 'find' images while rotating the sphere around.

Surely, the question is: how big do the radiators have to be?

gemini says that the NVIDIA DGX H100 is 130kg and takes 11kW.

It says space-based radiators in the 100kW range are approx 15kg per kW. And space-based solar panels are approx 1kg per kW.

So let's says we're talking about 1 system that bundles 9 DGX H100's. That's 1.2T for the computing system, 1.5T for the radiator, 100kg for the solar panels, and let's say 2T for the propulsion, propellant, guidance, and all the other spacecraft stuff. That's a total of about 5T, and the radiator is just about 20% of the mass budget.

The power radiated is proportional to the 4th power of the temperature, so they would be incentivized to develop a heat exchanger with a high temperature working fluid.

It will be used for spatial content, for viewing in Apple Vision Pro headset.

In fact you can already turn any photo into spatial content. I’m not sure if it’s using this algorithm or something else.

It’s nice to view holiday photos with spatial view … it feels like you’re there again. Same with looking at photos of deceased friends and family.

Access old ideas? Yes. With new perspectives?

I wonder if we can mine patent databases for old ideas that never worked out in the past, but now are more useful. Perhaps due to modern machining or newer materials or just new applications of the idea.

Trex makes composite decking planks from recycled shopping bags. Seems like a perfect use for the material. Its durable. It doesn’t have to be sterile or pure. Apparently 100,000 bags will go into a typical deck.

https://nextrex.com/

Having said that I don’t see what’s wrong with incineration if it’s done correctly. It’s not open pit burning, with waste gases going into the environment. It’s high temperature, with additional gas and oxygen to promote more complete burning. And waste gases are filtered.

I don't get why everyone keeps talking about the planets aligning. All the planets are pretty much in the same plane. So if you are on one of the planets, all of the others will always be in a line.

edit: to those downvoting me, can you explain why?

I see they are going for the high-end market. Seems the right path to me, for now, since they can charge high prices for foie gras without the guilt.

We eat beef, chicken, pork, and lamb, because they taste good, and are cheap to make because we can domesticate the animals.

What if exotic meats taste better, but we can't eat them because the animals are endangered, or dangerous, or undomesticable. Maybe lion, rhino, elephant, koala, meats etc taste really good. Growing these meats in the lab eliminates* these ethical problems.

Or what if they taste good, but they are too tough? Again, cultured meat process can interleave layers of fats to break up the muscle. Another win.

Just look at the nuance between the difference in taste between lamb and beef. There's so much difference, and I see so much potential here to explore different flavors.

* or maybe just exacerbates poaching, if it's cheaper to poach than grown in lab :/

But the "I am your father" wasn't in the shooting script anyway. The script said "Obi-Wan killed your father", and it was changed to "I am your father when James Earl Jones" said the line for the voice of Vader. Maybe it is that way in subsequent published scripts but not the original.

The smaller nuclear reactors used on submarines and aircraft carriers would be of the appropriate size, but they generate electricity using steam turbines. I don't think that would be workable in space. You'd need massive radiators to radiate away a lot of that heat to recondense the steam.

If you're generating that much heat, then you're probably better off using the nuclear reactor to directly heat the propellant.

Joe Scott has a new video up about Nuclear propulsion: https://www.youtube.com/watch?v=K5UU0GA5GAU

Why Not Mars 4 years ago

If a single mission to mars cost $100b, then I would agree with the article that it would probably not be worth it.

SpaceX is focused on reducing the cost, and no matter what you think of Elon, you have to agree that spacex focus on reusability in the falcon 9 has reduced their cost of access to space

The problem is that reducing spacex’s cost doesn’t reduce the customer’s cost… until there are competitors that can push the price down.

The focus on starship ultimately will reduce costs an order of magnitude again, and will permit vast payloads to mars.

Why does this matter? Because much of the cost of engineering of space missions is in custom making things to be light, power efficient and reliable.

If you can take more mass into space for less cost, you can add more solar panels into your design, make things more rugged, use off-the-shelf materials and you can double or triple the quantity for redundancy. Not only the launch costs go down, but all the associated engineering.

I think I ran into this "can't supply enough power" state last week. I was coming to the end of my ride, battery was around 15%. I was trying to slow down for a light that was turning red. I just couldn't make it slow down, and ended up hanging a right turn at 8mph then continued to speed up until 19mph. (in the mode I ride in, it's supposed to be limited to 12mph). It was terrifying. I was actively trying my best to slow down the entire time, but the board was going fast. After 15 or so seconds of this I bailed and walked away with a bit of road rash.

Totally different scenario from the CPSC complaint. But, yes, another way these machines are dangerous.

They used these thicker bags 20+ years ago, then went to the thin ones. Now we all figured out how useless those thin ones are. And we’re back to the thick ones.

It’s quite shocking visiting a place with no bag restrictions like Florida or Nevada, where they just automatically bag even the simplest purchase of tictacs.

I agree with the digital gold analogy. The value of bitcoin and other blockchain currencies is solving the double-spending problem online.

Gold and paper money solves it in the physical world. Gold because it’s dense and easy to check for forgeries (although gold is not used everyday now, is it). Paper money obviously has counterfeiting and serial numbers. But neither of these can be exchanged online.

If we agree that blockchain currencies are a way to exchange value online, then the question is: are they better than credit cards and banks?

Right now, it’s not clear to me that they are, because of the emissions from mining, and the relatively slow transaction rate. Time will tell if the digital currencies will scale better than they are now.

By the way, when comparing emissions of digital currencies with banks, do analysts include the physical bank infrastructure, such as all the bank’s retail branches, and associated employees and other overhead?

I used the Netscape/Mozilla NSS library quite a bit, and one problem I found with it, is that all of the DER encoding/decoding was written by hand. They should have generated all that boilerplate from the ASN.1 modules written in the specs (later, RFC 2459, but at the time, a hodge-podge of scattered specs).

Hand-coding works okay when the data is what you expect. But when you throw mal-formed certificates at it, you have to catch all the edge cases. Having generated code would have enabled much more edge cases to be covered.