Progenitor of the Weird Knife Wednesday feature column. Is “column” the right word? Anyway, apparently I also coined the Very Specific Object nomenclature now sporadically used in the 3D printing community. Yeah, that was me. This must be how Cory Doctorow feels all the time these days.
That’s how it works.
You may be thinking of “lazy loading,” where some scriptwork is used to delay downloading images until some time after the initial page load completes. This still requires all the data to be sent to the user — all of the data always has to be sent to the user eventually — but just not right away. This can have perceptible load time benefits, especially if whatever content you’re loading won’t be visible in the viewport initially anyway.
Oh, yeah. Or, if you’re very close to the horizon and reflecting light that’s already plowed through most of the atmosphere at a very shallow angle before it can hit the mirror satellite, how much attenuation you get from that. Tons, I’m sure.
Obligatory XKCD insertion.
This is one of those rare cases where regardless of where you place the hyphen, “old-ass clowns” or “old ass-clowns,” both are accurate descriptions of the clowns in question.
Nothing, which is why the letter phrases it as a “request.”
In order to be extradited he’d have to actually be charged with a specific crime, insofar as I am aware.
The same a what the sun already has to deal with, really. If your reflection and focus were somehow 100% perfect (impossible, but maybe you could get close) then attenuation from the atmosphere would be the same as what happens to ordinary sunlight over the same surface area, since that also has to pass through the same amount of atmosphere.
The Hubble is also in a rather low Earth orbit (340-ish miles), which enables it to use magnetic brakes which allow it to ditch the excess energy from its reaction wheels into the Earth’s magnetic field so it can stop pivoting when it aims. The further away you get from the planet the less effective that becomes. The bigger your object is, the bigger your reaction mass needs to be.
And the Hubble doesn’t inherently roast or blind innocent bystanders as it swings its point of aim across all of the intervening space between its targets. Maintaining a steady shine on one particular point on the surface is one thing, but these idiots seem to be implying that they will sell sunlight-as-a-service via some kind of subscription model to multiple customers, so they would presumably be changing targets all the time.
The Hubble can only rotate very slowly. Per the article, 90 degrees in about fifteen minutes. Its advantage is that it only looks at targets that are very far away and hold still relative to the Earth, so there is very little parallax to worry about. If you wanted to go faster you probably can’t use the reaction wheel method that it does; you’d have to use thrusters which would consume finite fuel that’d eventually (or quickly) run out, and at that rate there’s no way you could do it as accurately. For the Hubble specifically, the amount of time it takes to get on a target is broadly irrelevant, only that it can keep itself there once it eventually achieves targeting. This would not be so with the hypothetical solar reflectors, regardless of what altitude they were flown at. And low altitude orbits would be the worst, because they’d be flying over the target’s head at tens of thousands of miles per hour in terms of ground speed and would have to rotate very quickly in order to remain even vaguely pointed in the right direction.
Even if they could, the L1 point would be directly centered between the Sun and Earth on the already illuminated side of the planet, which is obviously not helpful. The L2 point would be on the other side of the Earth, on its dark side, and completely within its shadow so also not helpful.
From the L4/L5 points you would not only be rather far away but also only able to hit areas pretty close to the dusk line anyhow.
If you’re going to display pixels on the user’s screen, you have to send those pixels to the user. Magic still doesn’t exist. HTML img tags are indeed a “pointer,” but once the user’s browser has the path to that image file it will download the entire thing.
That said, there’s no reason to send an image that’s any bigger than it needs to be. Sending a scaled down thumbnail if you know it will be displayed small is sensible. Sending the entire 1200px wide or whatever image it is and just squashing it into a 100px wide box in the user’s browser is not.
First of all, I take a bit of umbrage at the author’s constant reference to “website size” without defining what this means until you dig into the FAQ. Just blithely referring to everything as “size” is a bit misleading, since I imagine most people would immediately assume size on disk which obviously makes no sense from a web browsing perspective. And indeed, they actually mean total data transferred on a page load.
Also, basically all this does is punish sites that use images. I run an ecommerce website (and no, I’m not telling you lunatics which one) and mine absolutely would qualify handily, except… I have to provide product images. If I didn’t, my site would technically still “work” in a broad and objective sense, but my customers would stage a riot.
A home page load on our site is just a shade over 2 megabytes transferred, the vast majority of which is product images. You can go ahead and run an online store that actually doesn’t present your customers any products on the landing page if you want to, and let me know how that works out for you.
I don’t use any frameworks or external libraries or jQuery or any of that kind of bullshit that has to be pulled down on page load. Everything else is a paltry (these days) 115.33 kB. I’mna go ahead and point out that this is actually less to transfer than jabroni has got on his own landing page, which is 199.31 kB. That’s code and content only for both metrics, also not including his sole image — which is his favicon, and that is for some inexplicable reason given the circumstances a 512x512 .png. (I used the Firefox network profiler to generate these numbers.)
Then you should fund my plan to build a giant magnifying glass and attach it to a blimp. Then we can fly over the ne’er-do-wells and zorch them.
That’s the main hurdle.
Re-finding this was a pain in the ass because I didn’t save it. https://lemmy.world/post/19485246/12219336
Editing to add some more meandering. Now this is even longer than the first one.
In addition to surface area limitations, there’s also a pretty obvious line of sight problem in that if your satellite is positioned such that its shiny side is facing the sun, by definition it must be facing the same direction as the Earth’s currently lighted side. The further past the dusk line onto the dark side of the Earth you’re trying to hit the further you have to rotate your mirror until ultimately the surface of it is perpendicular to the incoming sunlight. This is the angle of incidence, in optical terms, and it reduces the effective reflection not only off of the mirror proportionally to the increase in angle (in a roughly geometric manner, I believe) but also where that reflected beam of light hits the ground at its oblique angle. In real terms, it will be impossible to hit any target more than a few degrees past the dusk line with any meaningful amount of energy. Insofar as this harebrained scheme could possibly hit the ground with any amount of energy at all.
The diagram (which is surely not to scale) on these idiots’ website seems to depict a mirror in orbit around the Earth that’s about the size of Massachusetts, which is orbiting at a height that’d put it somewhere in the vicinity of the Van Allen belt, which is also a bad idea (no radio communication for you!) and would result in an orbital period of around 2.5 hours. If so, that means your mirror is whizzing over the surface at something like 14,000 MPH, and you would have some kind of line of sight to it from the ground for maybe 25% of its orbit. So even with the best will in the world and absolutely mathematically perfect rotation control it’ll only be able to remain on a surface target for about 37 minutes at most, most of which would be while it’s uselessly passing through the Earth’s shadow and is reflecting no sunlight at all, and for the remaining handful of minutes with its effective output tapering off to uselessness as it sets over the opposite horizon.
“I’ll just position my mirrors in a geostationary orbit,” says Mr. Clever. “Then I’ll have line of sight to a big chunk of the surface and my satellite won’t move relative to it.”
Well, the further you park your mirrors from the surface, the harder they are to aim. You can’t have it both ways. A geostationary orbit is about 22,000 miles from the surface, a distance from which even the tiniest error in alignment will result in you hitting the wrong target. You can use some middle school trig to calculate this for yourself: At a distance of 22,000 miles, an alignment error of just 0.01 degrees will result in the centerline of your beam missing the target by four miles, which in terrestrial terms is what we refer to as kind of a lot. Maintaining an alignment precision that high especially taking into account gravitational perturbation by the moon, etc., is a rather tall order. To maintain targeting precision within 223 feet, which is probably already unacceptable, you need a constant alignment precision of 0.0001 degrees, and you need to hold it there 100% of the time.
I don’t care how big your rocket is, that’s not happening.
All of this also assumes perfectly flat and 100% reflective surfaces on the mirrors, which never degrades or gets scuffed up or punctured by space debris. Which is also impossible.
To recap:
TL;DR: The whole thing won’t work.
In addition to being a moronic idea, this is also physically infeasible as I outlined in excruciating detail in my comment the last time this came up. The takeaway is that this is an investor scam for sure, and the side effects outlined in this article are just a fun (!) and exciting (!) sideshow if these bozos actually do mange to get a single mirror off the ground and deployed. Which they probably won’t.
Exciting enough for me to use on a daily basis, and I’m actively following their development progress. Not contributing, mind you. Nobody wants me of all people touching their codebase.
FreeCAD - The open source alternative to various proprietary parametric CAD and solid modelling software such as Solidworks, Fusion360, OnShape, etc. This recently passed its milestone 1.0 release at which point it could finally be considered actually broadly functional for actual real world use. Among various other widgets, I prominently used it to make this and this. Yeah, you guys know how it is.
I consider FreeCAD pretty important coming from the 3D printing hobbyist’s perspective because its the lone bulwark (well, okay, maybe also along with Blender and OpenSCAD) standing firm against the tidal wave of predatory bullshit being peddled by the commercial modelling software options, all of which at this point are genuine full-blown instruments of evil desperately trying to strangle, gatekeep, and paywall humankind’s ability to just make some goddamned shapes to 3D print.
In other news, I complied UZDoom from source the other night because somehow I missed that zdoom.org has precompiled binaries on their site, which I haven’t had to visit in years, but the UZDoom Github page doesn’t. We live and learn. UZDoom is pretty exciting because it’s a continuation of GZDoom with the added feature of kicking its insane former lead developer off of the project, or rather forking it out from under him. And everybody loves to play Doom.
Some AI or central computer going haywire and destroying everything is, like, the third or fourth stock RPG trope just behind the Dark Lord burning down the protagonist’s village in the first act or the mysterious waif girl actually turning out to be a princess.
You really think they’d know better.
Imagine my surprise and amusement to discover that https://www.realultimatepower.net/ is still online.
They already sell their vehicles to Altima drivers. I think doom was already on the menu.
Well, I do I have tucked into a random bookshelf one of those “World Atlas” book safes that everyone already knows is a storage box and not a book, because they’ve been sold virtually unchanged as far as I can tell since at least the early 1990s. As a little treat to anyone observant who notices this and thinks they’re so damn clever, inside I have nothing but a scaled down 3D printed replica of a cinder block.
It is astoundingly unlikely anyone will find where my valuables are actually hidden in my house, nor am I going to admit it on the internet.
Likewise, back when I built my first big pants real PC out of actual new components and not just hand-me-down bullshit cannibalized from decommissioned office stuff, I put the plethora of stickers that came with everything on the little rear triangle windows on my car. As if they were riceboy components instead, which in a way I suppose they were. Many of them were those textured stamped aluminum ones and they survived for quite a long time.
Surely at least one confused tuner saw this and puzzled over what the hell G.Skill and MSI “car parts” were supposed to do.
Here’s another sign of the times: Out of all the parts for my current rig, only two of them came with stickers. What a rip-off. My processor came with an AMD sticker (just a cheap vinyl one this time) and my motherboard came with an Aorus sticker which is at least textured metal. I stuck both of them to the inside of the front door on my case.
Deer aren’t very smart. I had one walk straight into the side of my car when I was stopped at a stop sign once. This didn’t do any apparent damage to either the deer or the car. Just, thump. When I mention this to other people around the area they inevitably have a similar story of a deer doing basically the same thing.
I don’t think evolution is working quite fast enough to be doing these dummies any favors just yet.
It’s the same line of logic as when you see people post on a forum something like [img]c:\Users\Bob\Documents\My_Image.bmp[/img] and then wonder why it doesn’t work.
“But I can see it on my computer!”
Over the internet, the origin of all data is on someone else’s computer. All means all. And all of it needs to come down the wire to you at some point.
You’re on the right track in one regard, though, in a roundabout way with caching: Browsers will keep local copies of media or even the entire content of webpages on disk for some period of time, and refer to those files when the page is visited again without redownloading the data. This is especially useful for images that appear in multiple places on a website, like header and logo graphics, etc.
This can actually become a problem if an image is updated on the server’s side, but your browser is not smart enough to figure this out. It will blithely show the old image it has in its cache, which is now outdated. (If you force refresh a webpage by holding shift when you refresh or press F5 in all of the current modern browsers, you’ll get a reload while explicitly ignoring any files already in the cache and all the images and content will be fully redownloaded, and that’s how you get around this if it happens to you.)