Restructure: USD fix + updated descendants

# [TECH] Rocket & Space Launch

**Rocketry** is the technology of reaction propulsion operating in vacuum, enabling satellite deployment, space exploration, and intercontinental ballistic missiles.

## Overview

Robert Goddard launched the first liquid-fuelled rocket (1926). WWII German V-2 (von Braun, 1944) proved large guided ballistic missiles were feasible. Sputnik (1957) opened the space age. Apollo 11 (1969) landed humans on the moon. Rockets deploy communication satellites, GPS, weather satellites, and Earth observation systems. SpaceX's Falcon 9 reusable first stage (2015) reduced launch costs by ~10× versus expendable rockets.

## Key Actors

- **Companies**: NASA (1958), Boeing, Lockheed Martin, SpaceX (2002), ULA, Roscosmos, Arianespace
- **Inventors**: Robert Goddard (1882–1945), Wernher von Braun (1912–1977)

## Key Patents

- Goddard, R. US Patent 1,102,653 (1914) — multi-stage rocket

## Economic Value

Global space economy: **\$USD 570 billion/year** (2023, Space Foundation). Commercial space launch market: \$USD 10B/year. GPS, satellite imagery, and satellite comms enabled by rockets: \$USD 500B+/year.

## Notes

Space Foundation *Space Report* 2023. SpaceX has reduced GTO launch costs from ~\$USD 65,000/kg (Space Shuttle) to ~\$USD 2,500/kg (Falcon 9 reuse), enabling the commercial space revolution.

## What This Enables

- **[TECH] GPS (Global Positioning System)** — GPS satellites are deployed into medium Earth orbit by rockets; their Keplerian + relativistic orbital mechanics requires Keplerian + GR correctionsis the system's foundation.
- **[TECH] Satellite Communications** — Communication satellites reach geostationary orbit (35,786 km) only via powerful launch vehicles.
- **[SCI] Gravitational Wave Astronomy** — Space-based GW detectors (LISA, planned 2035) and space telescopes providing EM counterparts require rocket launch.⏎
# Parents

* [SCI] Analytical Mechanics
* [SCI] Analytical Mechanics
* [TECH] Jet Engine
* [SCI] Classical Thermodynamics