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pieix

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GitHub: https://github.com/gordonhart

Co-founder: https://kolena.com

Atlas of Space: https://atlasof.space

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A huge portion of USPS international package volume is “ePackets” from China. These are a special service provided by USPS since 2011 for Chinese/HK goods that are cheaper and faster than normal USPS international shipping.

These ePackets are then bundled up into big sacks that are basically not inspected at all at US international mail facilities due to the de minimis exemption, which was just rolled back. The special status granted to ePackets meant that the volume shipped grew far beyond the processing capacity for normal packages at US IMFs. This pause (and subsequent unpause) from USPS on packages from China is because they don’t know how they’re going to handle that volume if it isn’t given special status.

Source: I worked on a project adjacent to this a couple of years ago. Close enough to pick up the basics but this isn’t quite what I was working on, so take my comment with a grain of salt.

The solution is to grow our way out of it — make more energy, make cleaner energy, develop new technologies — rather than browbeat people into submission with moral arguments because you don't like how they've chosen to deploy their resources.

AI isn’t a co-pilot; it’s a junior dev faking competence. Trust it at your own risk.

This is a good take that tracks with my (heavy) usage of LLMs for coding. Leveraging productive-but-often-misguided junior devs is a skill every dev should actively cultivate!

Elo on different card games/board games would be a great eval metric now that the systems are general enough to play Codenames, chess, poker…

Do you have any favorite Flutter projects I could click around? It’s an intriguing concept but I’ve been offput thus far by Google’s lack of adoption of its own framework.

Starship Flight 7 2 years ago

I might have missed it, but I’ve never seen a Soyuz booster fly twice, let alone 25 times.

Wasn't my intention at all to imply that they did something wrong and need to scramble to fix it. Just observing that a large portion of the web is built around the assumption that traffic is intermittent, where even a small burst of requests can knock it over. No shade — I've built plenty of sites like that.

Thanks for the feature request, guys — I just shipped a realtime clock with the ability to go backwards through time :)

Hey, thanks! I hadn't seen Celestia until another commenter mentioned it. Cool project, definitely some UX cues to take from it like the progressive hiding of labels and ellipses as you zoom out.

Thank you for sharing this with your family and for maybe increasing the number of space nerds on this planet! Exactly what I was hoping for with this project.

Thank you and not off topic at all, I was thinking this the whole time I was working on this project. The modern browser is magic.

Nice find. That's the only one up there currently, mostly because it's in a simple heliocentric orbit (most spacecraft are not). I want to add more but need to figure out how to properly find their current position+velocity to start the physical simulation.

Your edit is spot on — there's a lot out there in the Kuiper Belt / Oort Cloud that we don't know about. It's hypothesized that there are many objects out there, with more mass than in the Asteroid Belt. It's no coincidence that the ones we know are all near their perihelion currently.

Initial conditions are modeled by Keplerian elements around the main parent body. These are 6 scalars that describe the size, shape, and orientation of the orbital ellipse as well as the body's position along it at a given time (epoch). I scraped these values from various places including research papers, JPL databases, Wikipedia pages, and university web pages.

From there everything is mapped into a consistent epoch (now) and the initial position/velocity are calculated using a Keplerian->Cartesian transformation (the math here is a more or less straightforward coordinate transformation). The physical simulation is then run by updating these 2 Cartesian vectors, applying gravitational acceleration over ∆t.

This works pretty well, all things considered, but there's a lot of room for improvement to account for solar wind, relativistic effects, planets not being perfect spheres, etc. The Keplerian elements are also just an approximation of the true orbit, and this approximation can show up at high zoom levels (it's why planets don't always line up perfectly with their ellipses when you zoom in). I'm also still figuring out how best to get the initial position/velocity for objects that aren't in simple elliptical orbits (co-orbitals like the Trojans, objects on escape trajectories like Voyager probes). There's a lot for me to learn, maybe later I will write a blog post!

Three.js for all of the fun 3D stuff, vanilla canvas drawing for annotations like dots/labels/offscreen indicators. Three.js is an incredible project.

Fair point, I'll change (only after outing myself as somebody who pays more attention to writers than physicists)!

Appreciate the comment! The Expanse and Paul McAuley's Quiet War series both get a lot of inspiration credit for this project. I tried to include every body that has some "brand recognition", whether from fiction or from real spacecraft missions. There are actually quite a few asteroids and comets that have been visited in real life — NASA, ESA, and JAXA have been doing amazing things in the Asteroid Belt over the past few decades.

A big inspiration for this project was the "Solid Orrery" from Alastair Reynolds' Revelation Space series. I nearly went with this name!