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Eric Berger, senior space editor for Ars Technica [0], has written two books about Elon Musk and his role at SpaceX:

Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX [1]

Reentry: SpaceX, Elon Musk, and the Reusable Rockets that Launched a Second Space Age [2]

[0] https://arstechnica.com/author/ericberger/

[1] https://www.harpercollins.com/products/liftoff-eric-berger?v...

[2] https://benbellabooks.com/shop/reentry/

avhon1on AMD's trusted execution environment blown wide open by new BadRAM attack

> In some cases, with certain DIMM models that don't adequately lock down the chip, the modification can likely be done through software.

So on some systems, the hack could be performed entirely remotely.

avhon1on Desktop icons are surprisingly hard

Just wondering, what does this have to do with the article, which is about code that positions desktop icons on the screen (in KDE)?

avhon1on Only 5.3% of US welders are women. After years as a professor, I became one

So that there can be more welders?

avhon1on Starship Flight 5: Launch and booster catch [video]

Parachutes give little or no control over where and how the rocket lands, are unreliable (unfurling fabric behaves chaotically; modern spacecraft still don't have 100% reliability on their parachutes), and are surprisingly heavy.

Wings and landing gear are useless extra weight during launch, and excess weight on the booster has a super-linear reduction weight delivered to orbit. (the Tyranny of the Rocket Equation)

During the 1960s, NASA investigated using inflatable Rogallo Wings (basically hang gliders) to land the Gemini capsule. It worked fine, but was more complicated than parachutes, and re-use was not one of the goals of the Gemini or Apollo programs.

None of those give much margin for error on landing. Without any kind of propulsion, there's no option to come to a hover or do another go-around if the landing isn't going well. Space Shuttle pilots had to do extensive training in simulators for the landing because they only got one shot at it during the mission.

Propulsive landing doesn't require any hardware that isn't already on the launch vehicle, only a little excess propellant. (And it is a small amount; Super Heavy is like a soda can that's full of liquid at launch and only has a swig at the bottom during landing.) Propulsive landing gives Falcon 9 and Super Heavy the ability to overcome wind and other weather conditions to make pinpoint landings. Engine throttling gives Super Heavy the ability to hover, so it has a huge margin for error when coming in for a landing.

Super Heavy could have had legs, like Falcon 9, but it has such a huge payload capacity that they can simply choose to always launch with enough propellant to come back to the tower, and it saves a lot of flying weight and complexity by simply not having them. The arms on the tower can be massively overbuilt to ensure however much reliability SpaceX wants.

avhon1on Tcl 9.0

Lua is another language that lets you do this!

avhon1on In 1926, TV Was Mechanical

With pictures "made up of only 30 to 60 lines", they were transmitting much less data!

avhon1on OpenSCAD: The Programmer's Solid 3D CAD Modeller

Siemens Solid Edge is also available in a free community edition. https://resources.sw.siemens.com/en-US/download-solid-edge-c...

avhon1on I won't be renewing my Pinboard subscription

Zotero with the browser plugin

avhon1on [dead]

If you think that a 3-letter agency is making a concerted effort to tamper with your personal computers, then you basically can't trust anything about your computers at all, forever. What makes you think that your SSD actually got overwritten? How do you really know that the firmware you flashed actually has the correct signature?

Extra hardware could be hidden inside connectors, or packaged into re-labelled chips that look exactly like what you're supposed to find. The only end to it is if you:

1. stop using computers or depending on them to control anything about your life,

2. or build a computer (and all the necessary tools, etc.) entirely from resources which you either already trust or that you circularly prove are trustworthy (you'll have to do this in a totally secure workshop so that you know nobody tampers with your work before it's complete and you've sealed the computer shut),

3. or just give up on having total trust in your computers.

avhon1on Ask HN: Any hope for removable, rechargable battery standards?

These make tools run, but they're dangerous because they break the safety battery safety features which are built into the tool. With the exceptions of Ryobi and Makita, most power tool battery safety features are built in to the tools, and they communicate to the battery. At minimum, they check a thermistor. More sophisticated schemes can query the battery for shutoff voltage and maximum current.

avhon1on Synthetic diamonds are now purer, more beautiful, and cheaper than mined

Diamond turning is used to produce optical surfaces with lathes. Here's a recent example on youtube: https://www.youtube.com/watch?v=ZPTFFPLOzCw

avhon1on Synthetic diamonds are now purer, more beautiful, and cheaper than mined

Other mass-market uses for small rubies are for bearings in precision gear trains, and wear-resistant tips for precision measuring devices.

avhon1on Synthetic diamonds are now purer, more beautiful, and cheaper than mined

Sets like this one

https://www.amazon.com/dp/B092D4CV56

are also sold in U.S. hardware stores

https://www.harborfreight.com/needle-file-set-10-piece-69876...

https://www.menards.com/main/tools/hand-tools/files/tool-sho...

They are very cheaply made, but as far as I can tell are actually diamond. They're good for shaping glass and ceramics. For metal, you're better off using hardened steel files, but these ones will work, just slowly and with less precision.

avhon1on Fake CV lands top 'engineer' in jail for 15 years

It's legislated by individual states. A well-known example is Mats Järlström in Oregon, USA.

https://ij.org/press-release/oregon-engineer-wins-traffic-li...

avhon1on Show HN: High school robotics code/CAD/design binder release

Just to add, FreeCAD still doesn't ship with a way to do constrained assemblies of parts. You can arrange multiple parts together without any constraints on them, but if you want them constrained together then you have to pick an external workbench (there are 3 choices!) and install it separately.

https://wiki.freecad.org/Assembly

SolveSpace has the capability built-in, but its constraint and geometry solvers are not robust enough for designing full FRC robots. It either gets very slow, or start saying that constraints are unsolvable (even though they are), or starts generating geometry with extra or missing faces.

avhon1on Show HN: High school robotics code/CAD/design binder release

Commonwealth robotics studio doesn't seem to be suitable for designing typical FRC robots. It looks like it's meant to design and simulate robots that mostly consist of servo-driven legs around a central body.

The only open-source CAD option I've seen that might be suitable for doing this kind of design work is FreeCAD, or its Ondsel fork. There are not many people available to FRC teams to teach them how to use these programs, and there's a high risk of them running into serious bugs or limitations.

Most FRC teams use professional CAD packages (like Autodesk Inventor and Dassault SolidWorks). These packages are offered to teams for free. Many teams have mentors with professional experience using one of these programs. OnShape has taken over in the last couple of years as the most popular, because it is easier to license, doesn't require installation permissions, works on any device with a web browser, has an easy to understand and administer way for multiple people to collaborate on a model, and has a critical mass of community scripts, part collections, and tutorials.

avhon1on Clay (short for C Layout) is a high performance 2D UI layout library

It doesn't render anything for me in Firefox, just a blank white page. After a moment, a message shows up: "This page is slowing down Firefox. To speed up your browser, stop this page."

avhon1on Dual-screen laptops make more sense with this spiral notebook-like hinge

The known brands aren't much better. The Lenovo and Sony rootkits come to mind.

avhon1on SponsorBlock – skip sponsor segments on YouTube

Your definition slightly off. Here it is from the guy who coined the term:

https://pluralistic.net/2023/01/21/potemkin-ai/#hey-guys

> Here is how platforms die: first, they are good to their users; then they abuse their users to make things better for their business customers; finally, they abuse those business customers to claw back all the value for themselves. Then, they die.

Removing features is absolutely part of enshittification.

avhon1on An open-source flow battery kit

Every other year, (solar-)electric cars scratch-built by high school students drive on public roads from Texas to (usually) California. This is considered a reasonable level of challenge, and something which insurers will cover (entrants are required to have vehicle liability insurance).

https://www.solarcarchallenge.org/challenge/about.shtml

https://www.solarcarchallenge.org/challenge/docs/rules2023.p...

avhon1on An open-source flow battery kit

PowerWalls use NMC cells. And the majority of "diy powerwall" builds are reclaimed 18650 cells.

avhon1on NASA says Boeing Starliner astronauts may fly home on SpaceX in 2025

Here's what SpaceX put on their website before their most recent (fourth) flight test of Starship.

http://web.archive.org/web/20240601140837/https://www.spacex...

and here's what they posted before the third flight test

http://web.archive.org/web/20240306183144/https://www.spacex...

Both have pretty clear language about them being test flights (especially the flight 3 post), and list what they hope to test.

edit: they have not yet made an official page on their website for the upcoming fifth test flight

https://en.wikipedia.org/wiki/SpaceX_Starship_integrated_fli...

although they have teased about trying to return Booster to the tower for a catch attempt.

https://www.youtube.com/watch?v=j2BdNDTlWbo&t=149s

avhon1on Adding a USB port to the ThinkPad X1 Nano (the hard way)

The "strain" would depend on how many milliamps your 5V device draws. I don't know the current consumption of these logitech dongles, but it seems to be adequately low for this hack to work.

avhon1on FUTO Keyboard

Isn't performing paid work activities with a keyboard application profiting from using the keyboard?

avhon1on FUTO Keyboard

At least as often as old Android API versions being dropped.

More realistically, as often as bugs are identified and patched.

avhon1on Daylight Computer tablet review

The display is a (reflective) LCD, so the display latency should be low.

avhon1on Daylight Computer tablet review

Just to be clear, the daylight computer does not use e-ink. They call it an e-paper display, and it's basically a reflective LCD.

avhon1on Google has been blocking Invidious with error "This helps protect our community"

https://github.com/iv-org/invidious

> Invidious is an alternative front-end to YouTube

avhon1on Super Heavy has splashed down in The Gulf of Mexico

Exactly! Re-entry is the transition from orbital dynamics to aerodynamics. If you want the transition from orbit to flight to occur at a lower speed, then you need to be able to produce lift equal to your weight at that speed, at the altitude where you will hit that speed.