STARSOWN SCIENCE LIBRARY

How Starsown computes every world: stars, planets, orbits, rings and fields from real physics, with interactive models and every source credited.

How to read this library: What is computed, what is measured, and what is chosen
From a seed to a world: Random streams, rarity in bits, and a past that never changes
Stars: One star model, from birth to white dwarf, neutron star or black hole
A star that changes: Spin, magnetism and flares: why some stars stay calm and others erupt
Light, color and temperature: Why a star is the color it is, and how warm its planets are
Inside a world: Make-up, mass, gravity and shape
Rocky worlds: one recipe, many outcomes: one recipe, followed forward: where a world forms decides what it becomes
Giant planets: weather worlds and miniature solar systems: how a giant forms, cools and storms, and the moons and fields that make it a system of its own
Ice giants and the Neptunian worlds: why Uranus and Neptune are a kind of their own, the sub-Neptunes between them and rocky worlds, and the moons and fields they make
Super-Earths: the planets the Solar System skipped: the commonest size of planet, missing from ours: what they weigh, what they keep, how deep their water lies and how close they can go
Sub-Neptunes: the commonest planets: the planets the surveys find most, none of them ours: what they are made of, how heavy their air, why some are hazy, how they lose their hydrogen and what is left
Crowded systems: planets that share their star, packed close: how near they can sit, why they look alike, the chains of resonances that hold them and the heat their pull keeps
Whole systems: giants and the planets round them: cold Jupiters beside small planets, giants that follow their star’s metal, a giant’s slow pull on the orbits inside it, staying stable, lonely hot Jupiters, giants in resonance and the belts they carve
Hot Jupiters: giants a few days from their star: a day and night set by a race, clouds and rain by side, titanium trapped by night, an egg near its Roche lobe, metals escaping, spiraling in, orbits tilted to their star, and why no life
Super-Jupiters: giants of a few to thirteen Jupiters: why more mass barely means more size, hot and warm starts, deuterium’s brief burn, gravity and its sky, planet or companion, disks that make moons, why life is likelier on their moons, and the real ones
Super-Neptunes: worlds of 20 to 80 Earth masses, between Neptune and Saturn: the desert, ridge and savanna, why a runaway stops, one mass at many sizes, survivors and remnants, the mirror world, and the measured ones
Mega-Earths: solid worlds far heavier than a super-Earth: the box that names them, one mass and two sizes, the envelope that never came, deep inside, when a star’s spots can fake a mass, gravity you can see, and the measured ones
Sub-Earths: solid worlds smaller than Earth: a size class not a type, losing heat, Mars the archetype and Mercury the exception, exospheres and ice in the shadows, low-gravity terrain, lakes and the life that might have been, and the measured ones
Orbits, tides and moons: Kepler, Hill, Roche, and the slow work of tides
Rings and disks: Ice and rock inside the Roche limit, and disks around young stars
Magnetic fields and stellar wind: Where a planet’s field stops its star’s wind
Gravity in motion: How the sandbox moves every body
How the science has changed: Every version of the generator and the physics
Sources and thanks: The papers, data and code Starsown stands on

The library's models and diagrams need JavaScript. Meanwhile: sow a world · how to play · about.

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