For other uses, see Rocket (disambiguation).
A Soyuz-FG rocket launches from "Gagarin's Start" (Site 1/5), Baikonur Cosmodrome
A rocket (from Italian: rocchetto, lit. 'bobbin/spool')[nb 1][1] is a vehicle that uses jet propulsion to
accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust
expelled at high speed.[2] Rocket engines work entirely from propellant carried within the vehicle;
therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a
loss of thrust due to the opposing pressure of the atmosphere.
Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve
unlimited maximum altitude. Compared with airbreathing engines, rockets are lightweight and powerful
and capable of generating large accelerations. To control their flight, rockets rely on momentum, airfoils,
auxiliary reaction engines, gimballed thrust, momentum wheels, deflection of the exhaust stream,
propellant flow, spin, or gravity.
Rockets for military and recreational uses date back to at least 13th-century China.[3] Significant
scientific, interplanetary and industrial use did not occur until the 20th century, when rocketry was the
enabling technology for the Space Age, including setting foot on the Moon. Rockets are now used for
fireworks, missiles and other weaponry, ejection seats, launch vehicles for artificial satellites, human
spaceflight, and space exploration.
Chemical rockets are the most common type of high power rocket, typically creating a high speed
exhaust by the combustion of fuel with an oxidizer. The stored propellant can be a simple pressurized
gas or a single liquid fuel that disassociates in the presence of a catalyst (monopropellant), two liquids
that spontaneously react on contact (hypergolic propellants), two liquids that must be ignited to react
(like kerosene (RP1) and liquid oxygen, used in most liquid-propellant rockets), a solid combination of
fuel with oxidizer (solid fuel), or solid fuel with liquid or gaseous oxidizer (hybrid propellant system).
Chemical rockets store a large amount of energy in an easily released form, and can be very dangerous.
However, careful design, testing, construction and use minimizes risks.[citation needed]
History
Main article: History of rockets
Further information: Timeline of rocket and missile technology
Rocket arrows depicted in the Huolongjing: "fire arrow", "dragon-shaped arrow frame", and a "complete
fire arrow"
In China, gunpowder-powered rockets evolved in medieval China under the Song dynasty by the 13th
century. They also developed an early form of MLRS during this time. The Mongols adopted Chinese
rocket technology and the invention spread via the Mongol invasions to the Middle East and to Europe
in the mid-13th century.[4] According to Joseph Needham, the Song navy used rockets in a military
exercise dated to 1245. Internal-combustion rocket propulsion is mentioned in a reference to 1264,
recording that the "ground-rat", a type of firework, had frightened the Empress-Mother Gongsheng at a
feast held in her honor by her son the Emperor Lizong.[5] Subsequently, rockets are included in the
military treatise Huolongjing, also known as the Fire Drake Manual, written by the Chinese artillery
officer Jiao Yu in the mid-14th century. This text mentions the first known multistage rocket, the 'fire-
dragon issuing from the water' (Huo long chu shui), thought to have been used by the Chinese navy.[6]
Medieval and early modern rockets were used militarily as incendiary weapons in sieges. Between 1270
and 1280, Hasan al-Rammah wrote al-furusiyyah wa al-manasib al-harbiyya (The Book of Military
Horsemanship and Ingenious War Devices), which included 107 gunpowder recipes, 22 of them for
rockets.[7][8] In Europe, Roger Bacon mentioned firecrackers made in various parts of the world in the
Opus Majus of 1267. Between 1280 and 1300, the Liber Ignium gave instructions for constructing
devices that are similar to firecrackers based on second hand accounts.[9] Konrad Kyeser described
rockets in his military treatise Bellifortis around 1405.[10]
The name "rocket" comes from the Italian rocchetta, meaning "bobbin" or "little spindle", given due to
the similarity in shape to the bobbin or spool used to hold the thread from a spinning wheel. Leonhard
Fronsperger and Conrad Haas adopted the Italian term into German in the mid-16th century; "rocket"
appears in English by the early 17th century.[1] Artis Magnae Artilleriae pars prima, an important early
modern work on rocket artillery, by Casimir Siemienowicz, was first printed in Amsterdam in 1650.
