- Aphanites (adj. aphanitic; from Ancient Greek αφανης (aphanḗs) ‘invisible’) are igneous rocks that are so fine-grained that their component mineral crystals are not visible to the naked eye (in contrast to phanerites, in which the crystals are visible to the unaided eye). This geological texture results from rapid cooling in volcanic or hypabyssal (shallow subsurface) environments. As a rule, the texture of these rocks is not the same as that of volcanic glass (e.g., obsidian), with volcanic glass being non-crystalline (amorphous), and having a glass-like appearance.
- 5 steps to N-body simulation (alvinng4.github.io)
This is a series of tutorials inspired by the course “CFD Python: 12 steps to Navier-Stokes”. The goal is to teach beginners how to write fast and clean N-body gravity simulations code in Python.
- Mineral (Wikipedia)
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.