Liquid Oxygen (LOX) (O₂) is a cryogenic oxidizer propellant used as a oxidizer. Cryogenic — requires insulated tanks, boils off over time. Typical ISP: 270–460 s (depending on fuel) seconds.
Liquid oxygen is the most widely used oxidizer in rocket propulsion, employed in combination with nearly every major fuel type. It is produced by fractional distillation of air and must be stored at cryogenic temperatures below -183°C. LOX is used in virtually every modern orbital launch vehicle due to its high performance and relatively low cost.
First used in rocket engines by Robert Goddard in the 1920s. Has been the standard oxidizer since the dawn of the space age.
High performance, non-toxic, abundant, inexpensive, compatible with many fuels
Cryogenic boil-off, requires insulation, vigorous oxidizer requiring careful handling
