Project Hail Mary – Stellar Navigation Chart
valhovey.github.io
valhovey.github.io
Feature request: can you add WASD navigation? Arrow keys are weird on different keyboards. On mine they're squashed into the corner and not fun to use. WASD is the OG OP way to navigate. (WASDQE, where QE are the vertical plane, if you're into Unreal Engine key bindings.)
Examples of games that use HJKL are the text-based "graphic" adventures like NetHack, the Rogue series, and Linley's Dungeon Crawl. It is also used by some players of the Dance Dance Revolution clone StepMania, where HJKL corresponds directly to the order of the arrows. Gmail, Google Labs' keyboard shortcuts, and other websites use J and K for "next" and "previous".
And, thank you very much. This is super cool and exciting. I wish such a one exists for Asimov's foundation universe (fiction).
The planets around the stars, aside from our own solar system (obviously), are fictional-- both Tau Ceti and 40 Eridani are stars where we're looking for exoplanets, but we don't have strong evidence for either yet.
As 'on the nose' as 'Don't look up' was, we clearly need more content that inspires action than pits us to despair.
Andy did a fantastic job describing how nation-states might put aside their differences and work together to solve an existential crisis. Some of the events he imagined were just as awesome as they were unlikely in today's political climate.
ALL of that was distilled away in the movie. Like, LITERALLY ALL of it.
Lord Miller reduced the book to "Hot Homer in space and telepathic rock alien thing work together to save their planets." It was a beautifully crafted movie, but SO much dumber than it had to be.
IOW: it's intended to seem odd.
Sadly we live in a world where software engineer "stolen valor" now exists, where someone with no or little actual engineering ability will use ai to shit out something and then claim they made it themselves.
Not 100% certain that's happening here, but it can't be a coincidence that this site looks so much like a site I had AI create tracking other things in space, imo
You completely nailed it!! :)
I wanted to hook into the THREE object and explore the scene, but I wasn't able to figure out how to bring it back into scope after it's been optimized out of the js context, so instead I searched through the bundle to find where it unpacks the data and did that manually.
The power of computers comes at least partly from the fact that for many practical problems, they let you effectively pretend that resource constraints don’t exist at all.
My first proper computer (defined by programming on it) was a 3.5MHz single core processor with 48KB of RAM.
My current one is 16C/32T that can boost to 5.7GHz and has 64GB of RAM.
Considerably more than a million times the RAM and about a million times the processing power (if you factor clock speeds, core count, OOE, branch prediction, memory width and depending on workload etc).
I have more RAM in my house than every ZX Spectrum ever sold (about 5 million which comes out to ~240GB).
Adjusted for inflation a million spectrums (175 at 1982 prices) comes out to about 640 million quid.
My PC cost ~4000 in late 2022.
A million times faster for 0.000625% of the price, it’s been a hell of a ride.
Dealing with graphics has shadowed how hugely powerful the modern computers are. We're noticing now because of AI.
That said I think programmers do notice the performance outside of AI when they use software that surfaces how fast modern machines are which we do more than most.
I can remember when compiling a Linux kernel was “start it and go watch star gate” now I barely have time to boil the kettle for a cup of tea.
EDIT: TIL that the ecliptic plane of the Solar System is at an 60.2° angle to the galactic plane (https://en.wikipedia.org/wiki/Galactic_plane#/media/File:Mot...) - until now I somehow assumed that they were more or less parallel and never questioned that assumption. So it looks like the "main" plane is the ecliptic plane (which is of course very anthropocentric, after all the ecliptic plane doesn't really matter anymore once you leave the Solar System? But I guess that was they way it was shown in the movie?). Would be interesting to be able to switch to showing the galactic plane instead...
Something implicit in the diagrams of the galactic plane but not explicitly stated is that the solar system travels clockwise (retrograde) around the galaxy [0]. I find this unexpected as I thought the same "right hand rules" of planetary motion [1] were somehow connected to those of electromagnetism [2] and would apply upwards in scale.
The Sun follows the solar circle (eccentricity e < 0.1) at a speed of about
255 km/s in a clockwise direction when viewed from the galactic north pole at
a radius of ≈ 8.34 kpc about the center of the galaxy near Sgr A*, and has
only a slight motion, towards the solar apex, relative to the LSR.
1. https://en.wikipedia.org/wiki/Poles_of_astronomical_bodies
2. https://www.arborsci.com/blogs/cool/three-right-hand-rules-o...
Maybe it's harder than it seems. Does a definite galactic plane even exist? The ecliptic is defined by Earth's orbit, not a mean of all the planets. IIRC Sun's rotation plane is not aligned, not should it matter.
If there's a way to measure galactic plane, independently of Sun's orbit around the galaxy center (that also seems difficult to determine) it would involve measuring positions and trajectories of many very distant objects.
If you were using a 4k display and had the Sun and Alpha Centauri visible at opposite sides of the display, the orbit of Neptune would be in the same pixel as the Sun.
Also, I did a top-down pixel measurement, where I could see the distance to Tau Ceti as well as the orbit of Neptune. The radius of Neptune's orbit was 32px, while the distance to Tau Ceti was 1152px, for a ratio of 36, when in reality, Tau Ceti is 11.9 ly away, while Neptune has an orbit radius of 30 AU, which means Tau Ceti is around 25,000 Neptune orbits away, so the planet orbit scale is too big (or distance to other stars too small) by a factor of ~694 (25000/36)
Edit: Since this was top-down, the vertical displacement didn't factor into the distance, which also contributed to Tau Ceti appearing too close on screen, so the error is slightly better than that, maybe a factor of 600.
Edit 2: Tau Ceti is rendered at 3.652 pc × 3 world units/pc = 10.956 world units
Neptune’s orbit radius is rendered as 30.05 AU × 0.0065 world units/AU = 0.195325 world units
The rendered ratio is 10.956 / 0.195325 = 56.09 Neptune-orbit radii
The real ratio should be 25,067.5 Neptune-orbit radii
The scale error = 25,067.5 / 56.09 = 446.9×
"It's called space for a reason."
When I saw the series adaptation of The Expanse, it was really obvious they played a lot of artistic license to make it exciting. A real space battle would be dots firing invisible dots at each other. "Close quarter battle" would be within something like 2000 kilometers, maybe more. That is close.
This is noteworthy because The Expanse tried to get this better than other scifi, say Star Trek, Battlestar Galactica, or Star Wars (ok, space opera), where engagements take place at absurdly short ranges. In The Expanse you see the spaceships are really far apart, mostly dots to each other, and the engagements are (mostly) at really long torpedo ranges, with the exception of those cool scenes using PDCs. You get all those awesome shots where one spaceship sees the other as a tiny dot, then the camera zooms in dramatically to the other point of view. Cool!
And still, engagements are far too close range. But they "feel" long range in The Expanse, I think they got that visually right. I cannot blame them because I haven't seen anything any space combat in shows or movies that is even half as exciting and well done.
Jim Lovell would like a word.
The DPS-1 burn which restored the free return trajectory was done using the Apollo guidance computer.
The PC+2 burn which sped up the return from earth was done using the Apollo guidance computer.
The MCC-5 mid-course correction burn was done by hand.
The MCC-7 mid-course correction burn was done by hand, but used the Apollo guidance computer to integrate the accelerometer to let everyone know when the burn was done.
(All the burns on Apollo 8 were computer controlled. I'd assume Gemini 7 and 12 were hand flown, though I don't know for sure.)
Ultima (Proxima Book 2) by Stephen Baxter:
“Oh, come on. This is just great. An imperial Roman starship! . . . We know they lack sophisticated electronics, computers. I wonder how the hell they navigate that thing.”
“The drive isn’t always on,” said Titus.
Stef realized that a more precise translation of his words might have been, *The vulcans do not always vomit fire.*
“Every month they shut it down, and turn the ship.” He mimed this with his one good hand, like aligning a cannon. “The surveyors take sightings from the stars. Then they swivel the ship to make sure we’re on the right track, and fire up the drive again. It’s like laying a road, on the march. You lay a stretch, and at the end of the day the surveyors take their sightings to make sure you’re heading straight and true where you’re supposed to go, and the next day off you go. Works like a dream. Why, I remember once on campaign—”
“Navigation by dead reckoning,” said the ColU. “Taking sightings from the stars—simply pointing the craft at the destination. They have no computers here, Colonel Kalinski, nothing more complex than an abacus. And they have astrolabes, planispheres, orreries, sextants, and very fine clocks—all mechanical, mechanical, and remarkably sophisticated. But, Colonel, this starship is piloted using clockwork! However, if you have the brute energy of the kernels available, you don’t need subtlety, you don’t need fine control. You need only aim and fire.”https://www.youtube.com/watch?v=_c9W-icdTmg&list=PL66J-Gd5vt...
What officers do at the con once the ship is in motion is monitor ships systems and check for any external changes to the environment (such as other ships coming in for interception).
Of course astronauts are trained for it in simulators in case computers fail.
If there are ever real space battles, that’s actually the most ridiculous time to have humans flying. Human reflexes and ability to mentally model 3D space under microgravity and orbital mechanics are just categorically inferior to what any machine can do. We are too slow and too imprecise.
If there are pilots at all it’ll be at a higher level, like the piloting equivalent of a programmer commanding AI bots. The computer will present the pilot with a digested real time tactical and strategic abstraction and the pilot would make decisions at that level.
A computer or avionics failure in a space battle would probably just be fatal. Which would mean EMP weapons against computers might factor in heavily.
Nah, they'll have regulations forcing them to add artificial sound generators like today's EVs
I think that is we could maneuver spaceships like cars and get from place to place in seconds then we would engage at close distance. The only reason for keeping far away would be to have time to react to missile launches and attempt to intercept them. But that's not different than what ships do at sea.
Yes, that's why you would do it in space, too. The only reason sci-fi media doesn't do it is that it would look boring onscreen. You're just sitting there in the dark then all of a sudden a tungsten rod moving at some fraction of c vaporizes your hull, or a cloud of goo attaches to your hull and you bake to death slowly because you can't evaporate heat well enough. And of course actual lasers in a vaccuum are invisible.
But if your weapons outrange your enemy you will want to keep the range long. And if your weapons suffer less range penalty than theirs do you will want to keep the range long. The flip side being that if you're on the other side of either of these scenarios you want to keep the range short. And that's before you consider the effects of shielding--most universes with shields make them more effective against weaker attacks. This would mean that if you're facing lighter weapons than your own you keep the range open, if you're facing heavier ones you close.
Even by Star Wars standard that was absurd. What is this, a highway chase scene?
The background world building was pretty good from a hard SF point of view. Fusion rockets are possible and the high performance ones in the series are at the edge of physical plausibility but possible. Some of the details, like spinning up asteroids, don't work, but the basic physics of humanity's solar system build-out is mostly sound.
The rest of it gets increasingly soft and fantastic. Which is fine, it's fun space opera.
Earth, the belt, etc. would have infinite clean water, for example, and plenty of energy to grow food via hydroponics.
No one would have any issues refining metals or other materals, due to all the available energy. Etc. etc.
Setting aside magic, fictional science and technology aren't incompatible with hard sci-fi; in fact I'd argue that exploring those on "serious" terms is the entire point of the genre.
At some point I started seeing people advance this weird idea online that hard sci-fi means essentially nonfiction but that's not correct (or even sensible if you stop and think about it since at that point you're just writing a traditional character or political drama or whatever). It simply means taking a simulation style approach to various technological elements of the story. The deeper the simulation goes (ie the more nested levels of "okay and why does that work that way and what are the practical impacts on society") the "harder" the work is.
Magic is an interesting case. In theory it could be compatible with science but in practice the sort of phenomena that people usually mean by that term necessarily imply the intervention of some higher power.
You want to do an optimum burn for Earth -> Mars? Compute an ellipse such that one end touches Earth's orbit, one end touches Mars' orbit. Oops, Mars isn't going to be there, you wait. Once every 26 months you will find that half an orbit later Mars will be there, then you burn. We call this a launch window.
26 months later they will line up again, but neither Earth nor Mars are where they were before. A spacecraft in this second window will never pass anywhere near a crippled spacecraft that flew in the first window. Nor could they do anything but send a report if it did happen--if you're doing efficient burns you don't have the fuel to go to somebody's aid.
“Space ... is big. Really big. You just won’t believe how vastly hugely mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist, but that’s just peanuts to space."Although the Expanse did well in some areas, it had no battles that were as well written or as memorable as this one.
Come visit!
[1] https://eugenesciencecenter.org/exhibits/eugene-solar-system...
[2] https://montshire.org/exhibit/exhibits/outdoor-discovery-tra...
https://www.nsw.gov.au/visiting-and-exploring-nsw/locations-...
https://en.wikipedia.org/wiki/Solar_System_model#Permanent_t...
https://www.visitcorpuschristi.com/blog/post/things-to-do-on...
https://www.deutsches-museum.de/museumsinsel/programm/progra...
It is old, hence Pluto is still part of it
I so fondly remember him, as he was one of those people being a massive inspiration to my life.
[1] https://de.wikipedia.org/wiki/Planetenweg
Edit: Added scale.
Something like logarithmic distances would better capture information like "Am I about to crash into the star or enter a nice orbit" while still showing the full picture of where you are in relation to where you're going and where you came from.
No idea of that's what happened here, just a thought, I'm not an expert in starship computer interface design.
Similar to me books: Bobiverse, Long Way To A Small Angry Planet
I'm not a heavy reader
This site is cool, I want to get to know stellar navigation stuff for astrophotography watching a video like this where they pull up star charts to point the telescope at it pretty cool https://www.youtube.com/live/TexqPMQMyZg?si=oEnvrxW21-D0VXGV...
Tangent I'll throw in here, I never get the fabric folding gravity well diagrams as it seems to have a "down" direction, I guess it looks like it's down since it's a slice but the effect is an inward sphere?
see, it's not that easy to explain or visualise.
It's not like there is a "down" it's just you're looking at it from a top view?
Oh yeah another series would be Nick Webb Constitution (Legacy Fleet), I think I got farther into that series but didn't finish it unlike Bobiverse, maybe I did finish this trilogy, I haven't read books in a while honestly. That was a good series though I remember the depiction of the space battles.
Trying to be better at being in the moment vs. watching youtube/scrolling a website at the same time kind of thing
Yes, gravity is a vector field: every point in space near a heavy body has a vector pointed at the center of the body with a magnitude of the field strength. https://en.wikipedia.org/wiki/Gravitational_field
Whenever someone uses fabric sheet analogy, they need to shout that the X-Y of the sheet is a 2 dimensional analog of X-Y-Z space, and the Z direction of the sheet is the field magnitude, with the slope indicating direction.
All models are wrong, but some are useful (for understanding).
It talks about the distances and times involved and how time compression and astrophage infection rates work out. As a fan of the book and the movie it was nice to see the actual 3D star chart of everything. (warning: there may be spoilers there)
To me it seems like we’d need new physics (not just new technology) to have any chance of pulling this stuff off.
The book dodges these inconvenient numbers with a bit of a deus ex machina plot device that I won’t spoil here :)
From the wiki: Elite Dangerous has a 1:1 scale simulation of the Milky Way galaxy based on real-life scientific principles, scientific data and theories. It includes around 400 billion star systems, modeled on actual galactic charts. Planets and moons rotate and orbit with 1:1 scale in real-time, thus constantly changing a system's environment
I was completely immersed - it was a good way to spend a few days during lockdowns :)
I wanted to go to Sol, buy luxury goods...and take them to Barnards Star
The game came out at the start of my upper-sixth year so it often came up during his classes.
https://dwheeler.com/essays/project-hail-mary-map.html
My page shows a stellar map (from the viewpoint of Polaris) and a sky chart showing the key stars from Earth's viewpoint.
Source code (MIT license for my stuff) is at: https://github.com/david-a-wheeler/plot-stars
I wouldn't call it a "blog post" though, it's simply an essay. I update my essay whenever I decide it needs updating, and "blog posts" are usually chronological and fixed in time once posted.
Take care!
For the "how far?" https://www.aanda.org/articles/aa/full_html/2011/04/aa16141-...
We can get timing (rather than imaging) parallax...
> We find that with the first method a parallax with an accuracy of 20% or less can be measured up to a maximum distance of 13 kpc, which would include 9000 pulsars. By timing pulsars with the most stable arrival times for the radio emission, parallaxes can be measured for about 3600 ms pulsars up to a distance of 9 kpc with an accuracy of 20%.
(one kpc is 3261 light years)
Not only can they be detected at large distances, but measurements of how far can be done at greater distances than can be done with imaging ( https://www.youtube.com/watch?v=hFMaT9oRbs4&t=608s ).
I’ve seen proper star projectors from Zeiss but my ceiling is not a dome - plus expensive and requires infinite amounts of power..
I want all of the War Games original graphics. I know people have come a long way. But I want all of them.
The "Hackers" movie. "Sneakers". "The Matrix". These individual assets deserve to be preserved! They're iconic. They're art, in their own rights!
Edit: oh interesting. Apparently it was mentioned in the book as being affected by the astrophage. I forgot that tidbit and thought it was just a Star Trek reference.
It's also sort of the subject - and title! - of this great short story: https://clarkesworldmagazine.com/macleod_12_17_reprint/
The galaxy explorer/map in Elite: Dangerous is pretty good, I wish they would produce a stand-alone application of just the galaxy map, whether it's even close to correct or not, who knows, but it's enjoyable just to pretend you can move instantly between star systems and go exploringthe galaxy
I allowed WebGL and disabled Enhanced Tracking Protection and my adblocker, and still only the star labels appear.
Also, the dashed red line is --- SPOILER ALERT! ---- only part of the trajectory in the film, as there is another leg of the voyage not shown.
This is a great thing, but it's also a tell since we all saw the UIs people were building by hand pre-AI.
That said, I don't think it matters. What matters is whether it's low quality.
This appears to be the norm for US based scifi now. Glad I'm watching movies like The Wandering Earth and Alienoid instead.
It had a good premise. But it also fell apart immediately. Like, they only sent 3 people, 2 whom died on this UBER CRITICAL SAVE THE PLANET idea?
And Ryan Gosling's character is a fucking moron. You're supposed to be a molecular biologist, and you're basically a reddit-gag line?
Edit: lol -4 , like seriously, its a pretty bad show. I listed movies I compare it to. But no I get shit like "You must be fun at parties." Personal attacks, sigh.
???
/s, but I think I'm accurately describing the viewpoint you're responding to.
Hard not to see once you know about them, and they are indeed common.
But what should replace it? Good Nuanced writing? Good luck with that!
However in this example the contribution of the alien, not just to the whole saving the universe business, but to the actual story, the book, was huge.
American film having a single white male lead = not good.
That's a movie you watch while drinking, take a shot every time you see something absurd
I don't think the downvotes are because you expressed the view that the film is bad.
It's mainstream science fiction using tech we don't have. It will never make a lot of sense. And then you decide to bring skin colour/race into the discussion. What do you expect?
(I didn't downvote, you have a right to dislike a popular movie or book)
They explain why only 3 people (it's a bit contrived, but there's genetics involved), and why no more ships. It's an emergency, a resource and time-constrained mission on which a few things go wrong even before they depart. The world is on full emergency mode, rushing things and getting things wrong. The crew isn't even the initial pick, but there's an accident involved. The lead director believes she'll probably end up in prison after the mission launches. I don't know, it makes sense to me.
> And Ryan Gosling's character is a fucking moron. You're supposed to be a molecular biologist, and you're basically a reddit-gag line?
I think the meme-speak, which I also found a bit jarring, is simply Andy Weir's less-than-good writing style. I think Weir isn't a particularly good writer, but he managed to write an engrossing adventure which I enjoyed.
In-universe, molecular biologists and scientists in general do have sense of humor, enjoy memes, and are generally capable of doing and saying the dumbest things. So it also kind of works!
But, to be frank, I think it's also Andy Weir's style, because memes and pop culture references pop up even when it's not the character's PoV.
The thing about very smart people is that they can still manage to miss the bus.
And if you have read any of Andy Weirs other books they have a common theme of one person who’s in over their head who basically bumbles through by the skin of their teeth.