Every satellite in orbit made the same journey: from a clean room onto a rocket, through the atmosphere and into orbit. This guide explains, step by step, how satellites are launched into space, using real mission sequences described by NASA.
1. Preparation and integration
Before launch, the satellite is tested, shipped to the launch site and prepared in a clean room. It is mounted on a payload adapter and enclosed in the payload fairing, the nose cone that protects it during the ascent. The encapsulated payload is then attached to the rocket. Our article on the launch campaign describes this phase in detail.
2. Lift off and ascent
The rocket lifts off within its launch window. Most orbital rockets consist of several stages. The first stage, often supported by boosters, provides the high thrust needed to leave the dense lower atmosphere. On NASA's Roman Space Telescope launch on 30 August 2026, for example, the two Falcon Heavy side boosters shut down about 2 minutes and 24 seconds after launch, separated from the centre core and flew back to land near the launch site.
3. Staging
When a stage has used its propellant, its engines shut down and it separates. In the Roman launch, the centre core continued firing until main engine cutoff, after which the second stage ignited its Merlin Vacuum engine. Dropping empty stages is what makes reaching orbit possible, as explained in our guide to rocket staging.
4. Fairing separation
Once the rocket is high enough that aerodynamic heating and pressure no longer threaten the payload, the fairing halves are jettisoned. From then on, the satellite is exposed to space.
5. Orbit insertion
The upper stage accelerates the satellite to orbital velocity. According to ESA, a satellite at 800 kilometres altitude travels at approximately 7.5 kilometres per second. Many upper stages can restart their engines several times to reach the exact target orbit, for example a sun-synchronous orbit or a geostationary transfer orbit.
6. Separation and deployment
At the planned time and position, the satellite is released by its separation system. On rideshare missions, dozens of satellites can be deployed one after another. Small CubeSats are pushed out of dispensers by springs.
7. First contact and commissioning
After separation, the satellite switches on, deploys its solar arrays and antennas and makes first contact with a ground station. Operators then check all systems, a phase called commissioning, before the satellite starts its mission. Satellites delivered to a transfer orbit still have to raise their orbit with their own propulsion.
Sources
- ESA: Types of orbits
- NASA: Roman Space Telescope, Falcon Heavy Side Boosters Begin Return
- NASA Small Spacecraft Systems Virtual Institute: Integration, Launch and Deployment
- NASA: Basics of Space Flight
Cover image: A Falcon Heavy launches NASA's Nancy Grace Roman Space Telescope from Launch Complex 39A, 30 August 2026. Credit: NASA/Joel Kowsky (NHQ202608300010), public domain.