# tobari
Earth environment models — atmospheric drag density, IGRF geomagnetic field,
and space weather integration for orbital mechanics simulation. The name
「帳」(tobari) means "veil" — Earth's atmosphere and magnetosphere form the
environmental veil a spacecraft flies through.
Provides:
- Atmospheric density models (`Exponential`, `HarrisPriester`, `NRLMSISE-00`)
behind the `AtmosphereModel` trait, with typed `SimpleEci` position input.
- IGRF-14 full geomagnetic field + tilted-dipole approximation via
`MagneticFieldModel`.
- Space weather providers (CSSI, GFZ) feeding F10.7 / Ap / Kp indices into
the atmosphere models.