Viewing profile — ddahlen

Strictly from an energy conservation argument this doesnt make a whole lot of sense to me. Just some back of the envelope math if they take their current mirror size, make 50k of t…

You can put in a public comment on these changes here: https://www.federalregister.gov/documents/2026/05/29/2026-10...

I am a researcher studying orbital dynamics of asteroids/comets/dust. I made a very precise visualization tool for the solar system, it shows the motion of all of the known asteroi…

Research grade orbital mechanics, specifically of asteroids/comets. I've been working on it for 4 years now, finally tried using some AI tooling the last few months and ended up vi…

I suggest the appendix of the arxiv paper if you want to see some of the math required for solar system objects beyond simple Newtonian gravity (like Relativity corrections). I wro…

Its an implementation of a pretty standard integrator used by astronomers informally called "RADAU", but it is not exactly the same RADAU you would find elsewhere. Basically it is …

Working on orbital dynamics code for my PhD in astronomy, written in rust, it can accurately calculate the positions of all asteroids/comets to within a few meters. Today I am addi…

Here you go, here is its orbit from 1900 to 2100 in the earth's rotating frame, sun is at -1 on the x axis. https://dahlend.github.io/2025_PN7_Orbit_1900-2100.png Its hanging out f…

I made a 3D visualization of this a few weeks ago: https://dahlend.github.io/the_belt.html This includes about 1.3 million known asteroids (most of the known ones), so the page is …

One good reason to keep the raw data and orientation separate is hardware calibrations. I see some discussion here along the lines of "why not just flip the data before saving it",…

There are quite a few open source projects in astronomy, but in my experience there is a tremendous amount of code that is squirrelled away as it is difficult to reproduce and entr…

This is a Python (with Rust backend) library for high accuracy orbit calculation of the entire known catalog of asteroids. It is a full N-Body integrator, including lots of additio…

I am a professional astronomer, and I am running a survey for asteroids. This needs to be controlled from python, as it decides every night which objects to observe. I also heavily…

https://www.cambridge.org/core/journals/international-astron... Here is a heavily used method in astronomy, this involves a higher order polynomial expansion than RK4. This method …

This is really impressive! I considered buying a big harmonic drive mount for my scope, but the cost is really prohibitive. I have experienced the pain of getting ekos/kstars/indi …

It is neat to see some of the old work done in the field, this looks like a pretty classic treatment of the topic. It looks like they were using a fourth-order Runge-Kutta integrat…

Final edits of a paper at the moment, aim to submit next week. Perturbers are easy to add, though a little poorly documented at the moment. Additional physics right now are J2 of j…

I wrote a custom implementation of the Radau integrator, its been heavily modified. I have a lot of additional physics, it supports the non-gravitational models that JPL Horizons d…

Different goals, kete is meant to be aimed more toward observers and telescope data processing, all asteroids and comets at once on a laptop. Short term analysis (<100 years) and s…

Oort cloud comets are so distant that they are only weakly gravitationally bound to the solar system. When they come in and we see them, they have enough energy to go back out to t…

Eccentricity! You can approximate the orbits of basically everything in the solar system using 2-body mechanics (IE, ignore the planets). If you do this you get orbits which are el…

I'm one of those astronomers! I'm working on my PhD in orbital dynamics. A lot of people are requesting discretionary time on telescopes trying to get observations in. The orbit wi…

This orbit visualization uses a simple 2 body approximation, so only the sun. This is because unless an object has a VERY close approach to a planet the two body approximation is m…