Some universe development milestones edit

Big Bang nucleosynthesis
Sub-brown dwarf
Deuterium burning
Brown dwarf
Lithium burning
Robust associations of massive baryonic objects
T-Tauri star
Dwarf galaxy
Metallicity, Stellar population
Photodisintegration
Globular cluster
Blue straggler
Pair-instability supernova
Dwarf spheroidal galaxy
Dwarf elliptical galaxy
Lenticular galaxy
Irregular galaxy
Spiral galaxy
Giant elliptical galaxy
User:Robert Treat/leaving Earth as the Solar System evolves