Orbital flight - Definition

An orbital spaceflight (or orbital flight) in the general sense is a spaceflight where the spacecraft reaches the height of, and through having an appropriate velocity enters into, orbit around an astronomical body. Most commonly the term is applied specifically to Earth orbit: reaching Earth orbit from the Earth's surface.

In this latter sense, the expression "orbital spaceflight" is mostly used to distinguish from sub-orbital spaceflights, which are flights where the spacecraft reaches space but does not go fast enough to enter orbit. Note that the edge of space (100 km) is much lower than even the lowest orbital trajectories (c. 350 km). Also note that the required speed to "go orbital" (to achieve orbit with known methods) lies around 8 km/s (18,000 mph), while sub-orbital spacecraft may only fly at about 1.1 km/s to 1.3 km/s (2,500 mph to 3,000 mph). Refer to the article Difference between sub-orbital and orbital spaceflights for further information.

There are three main 'bands' of orbit: low Earth orbit, intermediate circular orbit and geostationary orbit.

Project HARP was a failed attempt, and a ram accelerator is another design, to launch an object into orbit with a gun, possibly with additional propulsion by a rocket.