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Project Hail Mary – Stellar Navigation Chart

valhovey.github.io

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Re: Project Hail Mary – Stellar Navigation Chart

#161

Post by jurakovic »

estetlinus wrote: post #71
ggreer wrote: post #9

Just FYI the sizes of the planets, stars, and their orbits are not to scale at all. To get an idea of how empty space is, there are 63,360 inches in a mile, and 63,239 astronomical units in a light-year. So if you scaled everything down such that Earth was 1 inch from the Sun, Neptune would be 30 inches away and Alpha Centauri would be 4 miles away. If you were using a 4k display and had the Sun and Alpha Centauri vi…

FYI we have a up to scale model of the solar system in Sweden https://en.wikipedia.org/wiki/Sweden_Solar_System Come visit!

There is also one in Zagreb, Croatia https://en.wikipedia.org/wiki/Nine_Views

Re: Project Hail Mary – Stellar Navigation Chart

#162

Post by hgoel »

JonathonW wrote: post #150
orsenthil wrote: post #117

Earlier quoted context omitted.

Since you built it, I am curious about the scientific accuracy of the movie, book and while taking the information GAIA DR3. I wanted to assume at least the stars part is science, but I think, there is a lot of fiction in that setting. Is this map the reality of what we know as science, since it came from GAIA DR3 dataset? And, thank you very much. This is super cool and exciting. I wish such a one exists for Asimov'…

The stars featured in the movie and in this chart (and in the book) are real, and reflect their real-world locations. 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.

IIRC at the time the book was written, there was some data suggesting a planet detection around 40 Eridani, but has been ruled out since then.

Re: Project Hail Mary – Stellar Navigation Chart

#163

Post by nunez »

orsenthil wrote: post #117
speleo wrote: post #56

Hi there! This is Val, I made the star chart. There's a little "about" blurb you can open in a modal on the site, but I wanted to mention that this demo uses the amazing GAIA DR3 dataset from ESA. I have a Python script that renders all 1.8+ billion stars into custom images, which is what I used for the skybox. The star positions and colors all use the GAIA data (save for a few bright stars not in the set). The data…

Since you built it, I am curious about the scientific accuracy of the movie, book and while taking the information GAIA DR3. I wanted to assume at least the stars part is science, but I think, there is a lot of fiction in that setting. Is this map the reality of what we know as science, since it came from GAIA DR3 dataset? And, thank you very much. This is super cool and exciting. I wish such a one exists for Asimov'…

The book does a significantly better job explaining the science behind the mission than the movie (which I found insulting, but I'm clearly in the minority of holding that opinion).

Re: Project Hail Mary – Stellar Navigation Chart

#164

Post by bugufu8f83 »

the_af wrote: post #85
QuercusMax wrote: post #63

Earlier quoted context omitted.

Babylon 5 was the only show in the 90s that actually had any sort of physics based space combat (as opposed to Star Wars-style "they're really just airplanes but we're pretending it's space").

I really missed on watching Babylon 5 (it was during my time, but I unfortunately dismissed it as just another Star Trek wannabe, and only learned later this was unfair). I wish I had given it a chance. I cannot watch it now because of several reasons, and I'm not sure it would stand the test of time anyway, after having watched The Expanse.

I personally think B5 is a better show than The Expanse, but I don't mind the dated visuals or the occasional bit of campy acting or whatever. The storytelling is absolutely first-rate.

Re: Project Hail Mary – Stellar Navigation Chart

#165

Post by Reason077 »

codesnik wrote: post #74
speleo wrote: post #56

Hi there! This is Val, I made the star chart. There's a little "about" blurb you can open in a modal on the site, but I wanted to mention that this demo uses the amazing GAIA DR3 dataset from ESA. I have a Python script that renders all 1.8+ billion stars into custom images, which is what I used for the skybox. The star positions and colors all use the GAIA data (save for a few bright stars not in the set). The data…

but why solar system is so out of scale?

Human-centric thinking.

Re: Project Hail Mary – Stellar Navigation Chart

#166

Post by hgoel »

ceheaaf wrote: post #125

For anyone who enjoys this, exploration in "Elite: Dangerous" (for which you need to be neither elite nor dangerous, exploration is peaceful) might be enjoyable for you as well. 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…

It's been a long time since I played, but I don't recall the motion of the planets mattering much. Supercruise lets you move fast enough that planets and moons that move enough to be noticeable are very easy to get to regardless.

Re: Project Hail Mary – Stellar Navigation Chart

#167

Post by Reason077 »

hnuser123456 wrote: post #22
ggreer wrote: post #9

Just FYI the sizes of the planets, stars, and their orbits are not to scale at all. To get an idea of how empty space is, there are 63,360 inches in a mile, and 63,239 astronomical units in a light-year. So if you scaled everything down such that Earth was 1 inch from the Sun, Neptune would be 30 inches away and Alpha Centauri would be 4 miles away. If you were using a 4k display and had the Sun and Alpha Centauri vi…

Mercury is orbiting partially inside the Sun, and Jupiter is nearly as wide as the Sun when it should be 1/10 as much, so the planet nodes should be scaled down 10x relative to 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 realit…

Also, since we're nit-picking, the positions of the planets are not being updated in real time. For example, I know that Venus and Jupiter are currently approaching conjunction: there are spectacular views of them both at sunset right now here in the Southern Hemisphere!

Re: Project Hail Mary – Stellar Navigation Chart

#168

Post by speleo »

dwheeler wrote: post #145

Those interested in this might also like my "Project Hail Mary Stellar Map" at: 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

Thank you so much for the blog post! I credited you in the about page, I used your charts as reference for the Astrophage infection graph view with the Petrova mode. I shared your blog with my friends, it was a great read.

Re: Project Hail Mary – Stellar Navigation Chart

#169

Post by hgoel »

waynecochran wrote: post #7

Very cool. On Voyager 2 we placed a map on the side of the probe that places the position of our sun based on an array of Pulsar stars (the map was designed by Carl Sagan). I noted in the PHM movie Rocky and Dr Grace made similar 3D maps (I think they were pulsars(?)). I guess pulsars form natural beacons that can be detected at large distances.

I thought the maps they made were of the neighborhood of stars around Tau Ceti, marking their respective home stars with the petrova line.

Re: Project Hail Mary – Stellar Navigation Chart

#170

Post by dylan604 »

foxglacier wrote: post #147
dylan604 wrote: post #50

Earlier quoted context omitted.

Sure, but why does this need to be to scale. Isn't the point more to get the humans a way of understanding where things are relatively? Navigating the map makes it interesting in being able to interactively see where some of the stars are relative to each other. Seeing Regulus and Castor/Pollux from this perspective is much different than on terra firma.

It can't do that if it's not to scale! And who knows where the errors are? Neptune's orbit is way too big compared to Alpha Centauri. Are other stars also way too close compared to that? I can't stand these intentionally misleading education images of stuff. You have to work at undoing the artistic license of the author before it's useful.

We seem to be conflating the actual navigation computer with a display to show the humans information. If it were to scale, it would effectively be useless to the human as the scale of space is just too damn big to fit in some sort of navigation display. However, the actual navigation computer can be as accurate as necessary to not become Lost in Space. That's an entirely different franchise
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