Lagrange points are fascinating to me and I feel they are underrepresented in science fiction, compared to how the space age ahead of us may play out.
The events of human history on earth have revolved in great part around settling at or controlling strategically advantaged locations, for example any coastline, or a geographic bottleneck for trade and travel (think of Singapore and the Strait of Malacca).
A Lagrange point is the simplest space-based analog to this that I know of, if you want to put something in a fixed location relative to other bodies, the Lagrange points are places where you can do it with the highest fuel economy. Then when operating from that position you will have more energy available to do other things, granting you advantage over competitors who are not at the Lagrange point.
So whether it's science, research, trade, defense etc. there is a compelling reason to locate things at a Lagrange point, and it seems this is already happening as we have science satellites at L1 and L2 and I believe L3 has been talked about. The Lagrange points are not all created equal in terms of distance to their respective bodies, size, energy required to maintain a position etc. All two body systems have them, so for example the Earth and Moon have a set of Lagrange points that are significant to us.
The LPs are what a lot of our space politics and problems may eventually revolve around (quite literally!).
> events of human history on earth have revolved in great part around settling at or controlling strategically advantaged locations, for example any coastline, or a geographic bottleneck for trade and travel
Not only that, it's easier to send mass between Lagrange points than it is to send it to them from either of the orbital bodies.
Getting from Earth to L1 or L2, each 1.5mm km away, takes 15 km/s, escape + 12 km/s. (You have to fight both the Sun and the Earth's gravity.) Getting from L1 to L2 takes less than 100 m/s. (L1 to L3, L4 or L5 about 1 to 2 km/s.)
This confers strong defensive first-mover advantages; it's energy-wise easier to hold five than take one from the Earth. (Obviously, it's mass-wise easier from the Earth.)
Relays at L4 and L5 (also described in the linked Wikipedia) would be useful. If both are built it's reasonable for relay stations or satellites stay in contact continuously, if over different paths at different times of the day. The second relay station would also be useful if other objects naturally collected within the regions of stability disrupt communication.
Lagrange points are a key plot device in Iain M. Banks’s The Algebraist. I did figure out the location of the Dweller wormhole pretty quickly, thanks to thinking about how Lagrange points worked, but it is a great work of science fiction.
Regarding sci-fi; Joshua "Lagrange" Calvert did a fancy maneuver in Peter F. Hamilton's Reality Dysfunction involving a lagrange point that gave him that nickname.
I always wondered what kind of fun treasure might be hiding in the L4 and L5 points. And what kind of secret missions were already sent there by various countries to look for stuff. There could be whole precious metal asteroids sitting around!
Thanks! I've been considering it (or enough detailed instructions to build one) since starting the project. I need to get a working model first though ;)
"The analysis revealed that both the CVR and FDR data were not recording during the four minutes leading up to the aircraft's collision"
How does this even happen where two systems would stop recording data. This story seems to get weirder and weirder. I'd always been under the impression that black boxes were really highly secure and extremely rigorously developed to specifically prevent data loss in situations like this.
Bad enough for the accident to occur, but to not have accurate telemetry and recorded data from the onboard systems is definitely going to make an already hard investigation very much harder
According to 737NG technical diagrams I found online, the CVR is powered by the XFER BUS 2, and the FDR by the DC BUS 1. Neither of these busses can operate from the battery, but both should be operating if either engine or the APU is running, provided all switches are in the correct position. On the surface it seems odd to not run the CVR/FDR from battery, but on the other hand it’s not a critical flight system.
This suggests either dual engine failure, or single engine failure followed by shutting down the wrong engine with the fire handle (which cuts off electrical power), or (unlikely) a catastrophic electrical system failure. This isn’t a new interpretation, since the ADSB transponder also shut down at about the same time which led many to assume the electrics had gone out for some reason. My guess remains that they shut down the wrong engine given that the reported bird strike occurred (reportedly) a few minutes before the plane seems to have lost power, but the timeline is still not certain.
However, it did seem like the engine that had the mobile footage with the compressor stalls was still running at landing which should usually be enough to generate electricity since even windmilling is enough, which adds another wrinkle. Perhaps the bird strike destroyed the generator?
Some recorders have a built in battery for exactly these cases (called Recorder Independent Power Supply), and (as I discovered while trying to figure out whether this exists) Canada seems to require them since 2023.
It might still give us some hints. In the other thread they say that the black box might have stopped recording because of a power failure - and planes manufactured before 2010 (this plane was from 2009) didn't need an UPS.
The hint that we get from this news is that the plane (or better, the blackbox) was missing electricity for 4 minutes prior to the crash.
Exactly, evolution also will leave things at "good enough for function". It may well be that our sleep cycle so happened to level off at "good enough" considering our other evolutionary constraints.
Definitely an area of study that seems interesting to me.
Ha! I said this the other day to a friend as well. The 'typical' (Mercator) view has Greenland looking nearly as big as the continent of Africa. Reality is that it's about 1/4 the size of the mainland US. Still a lot of land but not as big as a lot of people seem to assume.
I honestly have no idea how basic math (sphere to flat projection) escapes people.
TIL that the likeness of Einstein was licensed. Proceeds go to the Hebrew University of Jerusalem, which is fitting considering his support and investment:
"Albert Einstein is one of the founders of the Hebrew University of Jerusalem. To him, the university represented a combination of the commitment to his Jewish identity and his belief in the universal values of the pursuit of truth and respect for every human being."
On the one hand, about 8% of their students are from Palestine. On the other, they’ve repeatedly retaliated against students and faculty members for protesting and making anti-genocide statements, and the university is on Boycott Divest Sanction lists.
This is interesting and I don't doubt the problem exists, but just considering the physics of a person riding a bike, it seems tough to envision an effective safety system.
Maybe expanded use of those "bike airbag helmets"? I can't imagine a mountain biker wearing a bunch of bulky padding and still being able to participate in the sport.
> can't imagine a mountain biker wearing a bunch of bulky padding
XC or recreational trail riding, probably not, but if you're into enduro, freeride or downhill, you can (should) already be wearing a lot of really bulky gear. Heavy duty boots with toe protection, pads for your knees, hips, elbows, gloves, spine and chest protectors, neck braces, full face helmets with MIPS
I believe some kind of airbag solution could actually be really helpful, but here's the thing about falls in MTB: they happen quite often and they're usually harmless, sometimes you even toss the bike on purpose when you realize you've messed up or miscalculated a feature.
And you probably don't want to replace an expensive gas [generator] cartridge or suffer burns or just have to endure loud pops every time you make a mistake.
Aren't there materials out there that can change from "fluid" to "solid" based on electrical signals? Or maybe something like Oobleck instead. Then you could have some sort of spine-protector, that outlines/protects your back and is flexible by default, but if it can tell you're falling through the air somehow/rotating around, it starts being inflexible to protect the structure of your back.
I dunno, just brainstorming and have no experience building protective wear/devices.
I'm not a doctor, but I think most spinal injuries are caused by impact or compression from the axis of the spine (from one vertebrae to another). Not puncture injuries perpendicular to the torso.
> but I think most spinal injuries are caused by impact or compression from the axis of the spine
Yeah, that makes sense. I was thinking something that when expanded, would protect the bottom somehow + the top (maybe helmet is connected to this imaginary "spine protector"), so compressions would be really difficult on that axis.
TFA says most of the injured people were wearing pads and they went head-first over the handlebars. Reading between the lines, it sounds like they landed on their heads and the forces on their spine caused injury. Much like CTEs in football, you're going to have a hard time protecting yourself against inertia.
The article has most were wearing a helmet, but less than 10% other pads. I'm not clear on what other pads are, but they seem to include things like knee protection which I wouldn't expect to help in this type of accident (but probably help is much more common falls).
Mainly packaging and bundling everything together in one drop-in package for every day users to get access to. I've run Linux for 20+ years now, and gotten steam games working a few times over that period of time. Not hard, not impossible, but is probably more than the average Windows user wants to figure out.
SteamOS is really about bringing that final experience to the most number of people, and I am really supportive of their efforts!
https://en.m.wikipedia.org/wiki/Lagrange_point