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Submission + - China Recovers Orbital Rocket with Net Capturing System (spacenews.com)

hackingbear writes: The first Long March 10B rocket lifted off at 12:15 a.m. Eastern (0415 UTC) July 10 from Hainan Commercial Space Launch Site on the southern island province of Hainan. The China Aerospace Science and Technology Corporation (CASC) confirmed the successful recovery of the rocket’s first stage 11 minutes later, using a sea platform equipped with a net capture system, a world first. Videos emerging in the minutes following showed a controlled, powered descent with black smoke billowing from the top of the first stage, followed by capture by the Linghang Zhe (“navigator”) sea recovery vessel, with hooks deployed from the booster caught by a tensioned net. The recovery occurred six minutes after separation of the first and second stages. The full success of the flight with insertion of an unnamed satellite into orbit was confirmed by CASC more than 90 minutes after liftoff, representing a huge boost to both China’s desire to develop reusable rocket capabilities, and for its crewed lunar program. The five-meter-diameter, two-stage Long March 10B is 63 meters long, with a mass of 760,000 kilograms at liftoff and has a low Earth orbit payload capacity of 16,000 kg in reusable mode. The full, tri-core Long March 10 will be used to launch astronauts and a landing stack to the moon, with China committed to landing a pair of astronauts on the lunar surface before 2030.

Comment Re:Good for him (Score 2) 114

it will still be if it flourishes in china instead of in the us and the whole world, including the us, might still benefit from that knowledge. that "bummer" is just ideological ... which is all politics in the west seems to be about these days because objective reality doesn't make for a sellable story.

I don't think it's too rabidly nationalistic or ideological of me to say that I'd prefer such discoveries and technologies be developed in my own country, rather than importing them from China. From a scientific standpoint, I agree that the knowledge benefits everyone, no matter where the discoveries are made. But from the standpoint of economics and national security, every key technology that we have to import from a strategic rival is a potential liability.

Submission + - Converting Semi Trailers into Plug-In Hybrids (ieee.org)

necro81 writes: There are several companies, such as Tesla, trying to make semi trucks fully electric. The capital cost for such a truck, and the MW-scale infrastructure to recharge it, may be a hard sell for some operators. IEEE Spectrum reports that some companies are instead adding batteries and an electric motor to the semi-trailers that trucks haul behind them.

The Nivalis Powered Trailer Kit centers on an electric axle...rated at 50 kilowatts peak, capable of both propulsion assistance and regenerative braking. That axle draws on a 60-kilowatt-hour, 400-volt lithium-ion battery pack charged from three sources: the axle itself during braking and deceleration, a full-rooftop array of photovoltaic panels generating up to 3.7 kilowatts-peak, and a 32-amp, three-phase AC grid connection available during parking stops.

This approach is more akin to a plug-in hybrid: the truck may still be diesel-powered, but the electric assist from the trailer allows the truck to run more efficiently. Replacing diesel with kWh can save operators money while also reducing emissions. This incremental approach may be more accessible and less capital-intensive than replacing the truck itself.

Trailer Dynamics’s modular system offers three configurations ranging from 187 to 551 kilowatt-hours.... The M300 version [a 300-kWh battery] adds approximately four tonnes to the trailer.... Trailer Dynamics argues the weight penalty is largely academic in practice, because more than 90 percent of trailer movements are constrained by cargo volume before they approach legal weight limits.

Trailer Dynamics prices its system between €145,000 and €195,000 and targets a payback period of no more than five years. Nivalis targets five to six years at current costs.... Until someone publishes a full year of results from a trailer running in normal commercial rotation, fleet operators cannot answer the two questions that actually drives adoption: What does this cost, and when does it pay back?


Comment Re:Sounds like BS to me (Score 1) 37

The proposed technique may detect existing weapons, but how feasible is it to make an undetectable formula?

I'll quote myself from a different comment:

The detector works by looking for neutron spallation off the fissile material. You can't tweak the design to get rid of the fissile material. So to avoid detection you either need to 1) prevent the Van Allen or cosmic ray protons from getting in and causing the spallation, or 2) prevent the neutrons from getting out. Both involve a fair bit of shielding, which may simply be impractical.

Comment Re:Sounds like BS to me (Score 1) 37

But I would expect designs to get tweaked to avoid this type of detector.

The detector works by looking for neutron spallation off the fissile material. You can't tweak the design to get rid of the fissile material. So to avoid detection you either need to 1) prevent the Van Allen or cosmic ray protons from getting in and causing the spallation, or 2) prevent the neutrons from getting out. Both involve a fair bit of shielding, which may simply be impractical.

Comment Re:Sounds like BS to me (Score 1) 37

The Alpha-Radiation from Plutonium is already undetectable on the other side of a piece of paper. And, incidentally, Plutonium based nuclear weapons are lighter than Uranium based ones. Such a coincidence. Sounds to me like this person is full of crap.

Plutonium-based nuclear weapons usually contain uranium, too, as a tamper to aid in the original implosion, and/or as additional fissile material to boost yield. Here's a cross section of a US W87 warhead. Soviet designs weren't too different, because of espionage and physics.

I couldn't quickly find any sources that specifically discuss proton-induced neutron spallation in plutonium, but it is reasonable to expect that the effect would happen in fissile plutonium just like fissile uranium. Spallation from plutonium probably would have a different enough signature (i.e., a spectrum of neutron energies) that might even allow you to learn something about the bomb's internals.

Comment Re:Good news comrad! (Score 1) 37

I don't usually comment on AC posts. But this one beat me to the punch:

1) If the countermeasure is to jam the nuke's communications, then the obvious response is to rig the bomb to detonate automatically if it loses contact with command and control for too long.
2) But this approach only works as an effective deterrent if the other side - the one doing the jamming - knows that that will be the result.

In other words: it's very much like the ending of Dr. Strangelove.

Comment Re:Now do it for groceries (Score 2) 123

So the labels aren't going away. The ISPs will be required to advertise the highest amount they could possibly charge the customer, including all taxes and fees. And they'll be required to have those labels. The only thing going away is the requirement the label (not the price) be on the same page as the offering, and the ability to download the information in spreadsheet form.

The purpose of the itemized labels wasn't just to let consumers know how much their actual bill would be, rather than the advertised price. The itemized labels also made it harder for ISPs to hide their bullshit nonsense fees. What the heck even if a "broadband recovery fee" or a "convenience fee", and how does the ISP defend that being part of the bill? Now, it's just a "and here's all the extra stuff we're going to charge, justifiable or not, and we'll hide it in this one line item."

It's an informational asymmetry: the ISPs definitely know and have all the information - otherwise they couldn't generate a bill. But now the FCC is letting them obfuscate it. Properly functioning markets (which the GOP used to claim they cared about) rely on open and transparent pricing. This ain't it.

Comment Confused by claims (Score 3, Insightful) 49

I am confused by this company's claims. It sounds very much like a magnatorquer - a device that can change a spacecraft's orientation - that just happens to use superconducting magnets instead of, say, copper wire. That's cool, and will certainly have useful applications.

But then they start talking about using it for propulsion, which I'm confused by. To get propulsion pretty much always requires reaction mass - something you're throwing behind the spacecraft. This doesn't do that, so how is it supposed to produce thrust?

Comment Re:CAD software (Score 1) 242

Try that one: https://openscad.org/

That's neat, and I'm glad that it's out there. From the looks of it, it's a CAD program where you are using their scripting language to generate primitive solids and doing simple boolean operations on them (add, subtract, etc.). That could work for some things, but it sure seems tedious compared to CAD that offers a GUI. I also can't see that it allows for real parametric modeling, where this feature references this other feature (e.g., place a hole 4 mm from either edge of a corner; if the corner moves in space, the hole moves, too). It looks like you need to keep track of all that yourself in the scripting. I'm not sure how well it'll work with more complicated features, like defining rounds that follow edges, draft angles, and so on.

Comment It must be quite a redesign (Score 4, Informative) 23

Here is iFixit's guide for replacing the Switch 2 battery (last updated 9 May 2026). It is not a simple procedure - harder even than most smartphones I've had to deal with. JIS 00 screwdriver, head and prying to remove stickers, more screws, snap features to pry open - all just to get the case open. Then more screws, unplugging and removing components, some solvent to (hopefully) loosen the battery glue, so that by Step 36 you've removed the old one. A few more steps to install the new one, re-apply thermal paste (?!), reinstall and reconnect the internals, snap the case back together, reinstall fasteners, reapply stickers (if they hold!). Only 63 steps - piece of cake!

Changing this to make for an easy user replacement will be a substantial redesign. And this is all to the good.

Comment CAD software (Score 1) 242

I've used a number of (mechanical) CAD packages, and dabbled with PCB layout tools. I still use some today. The best ones are NOT available for Linux, and there are no OSS equivalents that come close. Even Creo (nee ProEngineer), which I first used on SGI workstations 25 years ago, no longer has a *nix version. Yeah, yeah, you kinda-sorta can get it to work if you are willing to endlessly tinker with virtualization. But there are almost always things that don't quite work right - namely graphics support. And why bother with all the headaches when you could just dual-boot into Windows and have it run natively

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