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Booster

The first stage of a rocket, which provides the thrust to get the vehicle off the pad and through the thickest part of the atmosphere.

Why it matters

The booster is the largest, most expensive and most reusable part of a launch vehicle, so it is where the cost of spaceflight is mostly decided. It burns for only a couple of minutes but does the hardest work, and it is the piece that lands back for reuse when a vehicle is designed for it. Booster reuse is the difference between throwing away the most valuable hardware on every flight and amortising it across dozens.

In our data

The concentration is easy to see in our own manifest. Falcon 9 alone accounts for 140 of the 350 missions we track - a single vehicle family, flying a recovered first stage on most of those flights, outnumbering every other rocket in the tracker combined. Electron adds 29 more and Vulcan 21. When people say launch has become cheap, what they are describing is mostly the reuse of one booster design.

Missions we track

2026-09-02 Falcon 9 Block 5 | Starlink Group 15-23 Launch Successful
2026-08-26 Falcon 9 Block 5 | Starlink Group 15-22 Launch Successful
2026-08-25 Falcon 9 Block 5 | Starlink Group 10-49 Launch Successful

Where we use it

Not to be confused with

Strap-on solid rocket motors, which are also called boosters in some vehicle families, and the upper stage, which takes over after the first stage separates and is almost always expended.