Learning & Exploration

In astronomy, first light is the moment a new telescope captures its very first image of the sky. It marks the instant when months of building and calibrating finally produce something real.

This section is your first light. You do not need a physics degree to understand how orbits work. The resources here will get you from “I saw the ISS fly over” to “I understand why its orbit precesses” — and you will have fun getting there.

Tip

If you are brand new to all of this, start with Scott Manley’s YouTube channel. He has a gift for making orbital mechanics click.

Watch & Listen

The best explanations of orbital mechanics come from people who genuinely love the subject. These channels cover everything from Kepler’s laws to real launch trajectories, with visuals that make the concepts stick.

Scott Manley Former astronomer who explains orbital mechanics through KSP gameplay and real launch coverage. The gold standard for accessible space content.

PBS Space Time Deeper physics -- Kepler's laws, Lagrange points, gravitational assists -- with production quality that keeps you watching.

Kurzgesagt (space episodes) Beautiful animations explaining scale, orbits, and space exploration concepts. A great first exposure if the math feels intimidating.

ASU AEE 462 -- Orbital Mechanics A full university course, free on YouTube. For when you want the real math with a professor walking you through each derivation.

Interact & Simulate

Reading about eccentricity and inclination only goes so far. These tools let you drag orbits around and watch the math update in real time — the fastest way to build intuition.

Orbit Architect Browser-based orbit designer. Draw an orbit, adjust parameters, and see Keplerian elements update live. Best tool for understanding what each orbital element actually controls.

OrbitalMechanics.info Interactive orbit simulator with Hohmann transfers, inclination changes, and mission design. Complex enough to be useful, simple enough to not be overwhelming.

NAAP Kepler's Laws Simulator University of Nebraska astronomy applet. Drag planets, reshape orbits, and watch Kepler's three laws play out in real time.

Note

Kerbal Space Program deserves a mention here. It is not a website — it is a game — but more people have developed genuine orbital mechanics intuition from KSP than from any textbook. If you have ever wondered why you burn prograde at periapsis, KSP is where that question becomes visceral.

TLE Demystified

Two-Line Element sets are the standard format for describing a satellite’s orbit. They look cryptic at first — 69 characters per line, no labels, column-position encoding — but each field has a purpose. Craft’s own TLE Format reference covers the structure in detail. These external resources explain the why behind each field:

KeepTrack TLE Tutorial Visual walkthrough of every TLE field with color-coded examples. Seeing each field highlighted in context makes the format click faster than any table.

CelesTrak TLE FAQ Dr. T.S. Kelso's definitive FAQ, written by the person who operates the primary TLE distribution service. The authoritative reference.

Satellite Signals TLE Guide Quick-reference table format that maps each column position to its meaning. Good for printing and keeping next to your terminal.