Neutron is a partially reusable medium-lift two-stage launch vehicle under development by Rocket Lab. Announced on 1 March 2021, the vehicle is designed to be capable of delivering a payload of 13,000 kg (28,700 lb) to low Earth orbit in a partially reusable configuration, and will focus on the growing megaconstellation satellite delivery market. The vehicle is expected to be operational sometime in 2025. It uses LOX and liquid methane propellant on both stages of the vehicle.