Transport & space · 1903
Rocket equation
Tsiolkovsky proves on paper that rockets can reach orbit, and how.
In 1903 Konstantin Tsiolkovsky published the relation between a rocket's velocity change, exhaust speed and mass ratio. He showed multistage liquid-fueled rockets could reach orbital speed. His work laid the theoretical foundation for Goddard, Oberth and Korolev.
What it built on 2
What it led to 1
Related measurements
The dashed line marks when it first worked.
Objects launched into space Latest: 4.51k per year (2025) Source: Our World in Data