space.prabasiva.ai
Space Technology Notes
A working knowledge base on space technology. Ten subject areas, from the physics an orbit rests on through the engineering that flies and the industry that pays for it, plus an open lab of notes, derivations, simulations and experiments in progress.
Most of this site is currently a skeleton. Every page carries a status marker, so you always know whether you are reading a placeholder or finished work.
Gravitation, escape velocity, Kepler’s laws, Lagrange points, relativity where it matters, radiation, vacuum and the space environment.
02Orbital MechanicsElements and state vectors, transfers, delta-v, plane changes, rendezvous, station keeping, perturbations and trajectory optimization.
03Launch and PropulsionThe rocket equation, chemical and electric propulsion, engine cycles, nozzles, nuclear systems and reusable launch.
04Spacecraft EngineeringPower, thermal, avionics, communications, GNC, structures, life support and fault tolerance, held together by systems engineering.
05Satellites and ConstellationsOrbit regimes, CubeSats, constellation design, Earth observation, GNSS, communications satellites, debris and the ground segment.
06Exploration and MissionsThe Moon, Mars, Venus, small bodies, the outer planets, space telescopes, Artemis and sample return.
07Astronomy and AstrophysicsStars, galaxies, black holes, exoplanets, cosmology, dark matter, telescopes and observational method.
08Space InfrastructureStations, lunar and Mars surface systems, in-space manufacturing, propellant depots, space solar power and orbital compute.
09Space Economy and IndustryLaunch markets, agencies, commercial providers, venture capital, unit economics, policy and regulation.
10Space Computing and AIAutonomy, AI planning, computer vision, image processing, edge compute, robotics, digital twins, simulation and data platforms.
11EntitiesOrganizations, companies, programs and people, recorded once and linked from everywhere else.
12Research and Learning LabNotes in progress, open questions, paper reviews, experiments, simulations, derivations, code and diagrams.
How the site is organized
The first ten sections are subject areas: stable reference material, written once and revised. The lab is the working surface, where a topic starts as a raw note and only moves into a subject section once it is coherent and checked.
Conventions
Derivations are written out rather than quoted. Where a result matters, it is set apart and named, so it can be referred to from elsewhere on the site. The vis-viva equation, which most of the orbital mechanics section leans on, is the first of them:
Diagrams are authored as Mermaid source inside the page, never pasted in as images, so they stay diffable and editable in version control. Math is written in LaTeX and rendered with KaTeX. Units are SI unless a field convention makes that perverse, in which case the convention is stated.
Where to start
If you are new to the material, read Space Fundamentals in order, then Orbital Mechanics. If you are looking for something specific, use search. If you want to see what is actively being worked on rather than what is finished, go to Questions I am exploring.