CometsFactory

Procedural comet generator for the Celestial Bodies ecosystem.
Build, classify, and catalogue comets of every dynamical family — from Jupiter-family short-period comets to interstellar visitors.

Architecture

Module	File(s)	Purpose
config	`parameters.rs`	Physical constants, orbital helpers, sublimation constants
types	`short_period.rs`, `long_period.rs`, `halley_type.rs`, `sungrazer.rs`, `interstellar.rs`, `main_belt_comet.rs`, `centaur_transition.rs`, `extinct.rs`	8 comet types with builder pattern
physics	`gravity.rs`, `sublimation.rs`	Binding energy, tides, Roche limit, sublimation rates, gas production, non-grav acceleration
engine	`orbits.rs`, `evolution.rs`, `coma.rs`	Keplerian propagation, mantle growth, spin-up, coma/tail modelling
observables	`photometry.rs`, `tail.rs`	Total/nuclear magnitudes, Afρ, dust/ion tail orientation, disconnection events
utils	`helpers.rs`, `io.rs`	Angle conversions, summary lines for all 8 types

Comet Types

#	Type	Key Features
1	ShortPeriod	Jupiter-family comets, P < 20 yr, 2 < T_J < 3
2	LongPeriod	Oort Cloud origin, P > 200 yr, dynamically new flag
3	HalleyType	20 < P < 200 yr, T_J < 2, retrograde detection
4	Sungrazer	Kreutz/Marsden/Kracht/Meyer groups, tidal disruption
5	Interstellar	Hyperbolic orbits (e > 1), excess velocity
6	MainBeltComet	Asteroid-like orbits (T_J > 3), sublimation-driven activity
7	CentaurTransition	CO-driven outbursts, giant-planet region, dynamical lifetime
8	Extinct	Dormant/extinct states, mantle thickness, reactivation potential

All types expose a builder pattern: new() → with_*() chainable methods.

Usage

use cometsfactory::types::*;

let jfc = ShortPeriod::new(500.0, 3.5, 0.6)
    .with_density(600.0)
    .with_inclination(10.0)
    .with_active_fraction(0.03);

assert!(jfc.is_jupiter_family());
assert!(jfc.perihelion() < jfc.semi_major_axis);

use cometsfactory::physics::sublimation;

let q = sublimation::gas_production_rate(1000.0, 0.05, 1.0, 0.04);
assert!(q > 1.0e20);

Tests

73 tests across 3 test suites:

types_tests — 38 tests (builders, orbital properties, classifications)
physics_tests — 14 tests (gravity, sublimation, thermal)
engine_tests — 21 tests (orbits, evolution, coma)

cargo test --all-targets

Examples

Example	Description
`generation`	Creates all 8 comet types, exercises enum dispatch
`physics`	Gravity + sublimation computations on a Jupiter-family comet
`observables`	Photometry, Afρ, dust/ion tails, disconnection events

cargo run --example generation
cargo run --example physics
cargo run --example observables