Hubble Space Telescope over Earth (during the STS-109 mission)

Astronautics (or cosmonautics) is the theory and practice of travel beyond

Earth's atmosphere The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing fo ...

into

outer space Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies. Outer space is not completely empty—it is a near-perfect vacuum containing a low density of particles, pred ...

Spaceflight Spaceflight (or space flight) is an application of astronautics to fly spacecraft into or through outer space, either with or without humans on board. Most spaceflight is uncrewed and conducted mainly with spacecraft such as satellites in o ...

is one of its main applications and space science its overarching field. The term ''astronautics'' (originally ''astronautique'' in French) was coined in the 1920s by J.-H. Rosny, president of the Goncourt academy, in analogy with aeronautics. Because there is a degree of technical overlap between the two fields, the term

aerospace Aerospace is a term used to collectively refer to the atmosphere and outer space. Aerospace activity is very diverse, with a multitude of commercial, industrial and military applications. Aerospace engineering consists of aeronautics and astr ...

is often used to describe both at once. In 1930,

Robert Esnault-Pelterie Robert Albert Charles Esnault-Pelterie (8 November 1881 – 6 December 1957) was a French aircraft designer and spaceflight theorist. He is referred to as being one of the founders of modern rocketry and astronautics, along with the Russian Kons ...

published the first book on the new research field. The term ''cosmonautics'' (originally ''cosmonautique'' in French) was introduced in 1930s by

Ary Sternfeld Ary Sternfeld (14 May 1905 – 5 July 1980) was co-creator of the modern aerospace science. He was a Polish engineer of Jewish origin, who studied in Poland and France. From 1935 until his death he worked in Moscow. He was the first person to ...

with his book ''Initiation à la Cosmonautique'' (Introduction to cosmonautics) (the book brought him the Prix REP-Hirsch, later known as the Prix d'Astronautique, of the

French Astronomical Society French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with France ...

in 1934.l'Astronomie, 1934, p. 325–326.
/ref>) As with aeronautics, the restrictions of mass, temperatures, and external forces require that applications in space survive extreme conditions: high-grade

vacuum A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or " void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often di ...

, the radiation bombardment of

interplanetary space Interplanetary may refer to: * Interplanetary space, the space between the planets of the Solar System *Interplanetary spaceflight, travel between planets *The interplanetary medium, the material that exists in interplanetary space *The InterPlane ...

and the magnetic belts of

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...

. Space launch vehicles must withstand titanic forces, while satellites can experience huge variations in temperature in very brief periods.''Understanding Space: An Introduction to Astronautics'', Sellers. 2nd Ed. McGraw-Hill (2000) Extreme constraints on mass cause astronautical engineers to face the constant need to save mass in the design in order to maximize the actual payload that reaches

orbit In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as ...

History

The early history of astronautics is theoretical: the fundamental mathematics of space travel was established by

Isaac Newton Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a " natural philosopher"), widely recognised as one of the grea ...

in his 1687 treatise '' Philosophiæ Naturalis Principia Mathematica''.''Fundamentals of Astrodynamics'', Bate, Mueller, and White. Dover: New York (1971). Other mathematicians, such as Swiss

Leonhard Euler Leonhard Euler ( , ; 15 April 170718 September 1783) was a Swiss mathematician, physicist, astronomer, geographer, logician and engineer who founded the studies of graph theory and topology and made pioneering and influential discoveries in ma ...

and Franco-Italian

Joseph Louis Lagrange Joseph-Louis Lagrange (born Giuseppe Luigi Lagrangiapractical discipline Applied science is the use of the scientific method and knowledge obtained via conclusions from the method to attain practical goals. It includes a broad range of disciplines such as engineering and medicine. Applied science is often contrasted ...

until the mid-20th century. On the other hand, the question of

spaceflight Spaceflight (or space flight) is an application of astronautics to fly spacecraft into or through outer space, either with or without humans on board. Most spaceflight is uncrewed and conducted mainly with spacecraft such as satellites in o ...

puzzled the literary imaginations of such figures as Jules Verne and

H. G. Wells Herbert George Wells"Wells, H. G."
Revised 18 May 2015. ''

Russian cosmist Russian cosmism, also cosmism, is a philosophical and cultural movement that emerged in Russia at the turn of the 19th century, and again, at the beginning of the 20th century. At the beginning of the 20th century, there was a burst of scientific ...

Konstantin Tsiolkovsky Konstantin Eduardovich Tsiolkovsky (russian: Константи́н Эдуа́рдович Циолко́вский , , p=kənstɐnʲˈtʲin ɪdʊˈardəvʲɪtɕ tsɨɐlˈkofskʲɪj , a=Ru-Konstantin Tsiolkovsky.oga; – 19 September 1935) ...

derived the

rocket equation A rocket (from it, rocchetto, , bobbin/spool) 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. Rocket engines work entirely fr ...

, the governing equation for a rocket-based propulsion, enabling computation of the final velocity of a rocket from the mass of spacecraft (

m_1

), combined mass of propellant and spacecraft (

m_0

) and exhaust velocity of the propellant (

v_e

). :

\Delta v\ = v_e \ln \frac

By the early 1920s,

Robert H. Goddard Robert Hutchings Goddard (October 5, 1882 – August 10, 1945) was an American engineer, professor, physicist, and inventor who is credited with creating and building the world's first liquid-fueled rocket. Goddard successfully laun ...

was developing liquid-propellant rockets, which would in a few brief decades become a critical component in the designs of such famous rockets as the

V-2 The V-2 (german: Vergeltungswaffe 2, lit=Retaliation Weapon 2), with the technical name ''Aggregat 4'' (A-4), was the world’s first long-range guided ballistic missile. The missile, powered by a liquid-propellant rocket engine, was develope ...

and

Saturn V Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with three stages, and powered with liquid fuel. It was flown from 196 ...

. The Prix d'Astronautique (Astronautics Prize) awarded by the Société astronomique de France, the French astronomical society, was the first prize on this subject. The international award, established by aviation and astronautical pioneer

and André-Louis Hirsch, was given from 1929 to 1939 in recognition of the study of interplanetary travel and astronautics. By the mid-1950s, the

Space Race The Space Race was a 20th-century competition between two Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the t ...

between the USSR and the US had begun.

Subdisciplines

Although many regard astronautics itself as a rather specialized subject, engineers and scientists working in this area must be knowledgeable in many distinct fields. *

Astrodynamics Orbital mechanics or astrodynamics is the application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets and other spacecraft. The motion of these objects is usually calculated from Newton's laws of ...

– the study of orbital motion. Those specializing in this field examine topics such as spacecraft trajectories, ballistics and celestial mechanics. * Spacecraft propulsion – how spacecraft change orbits, and how they are launched. Most spacecraft have some variety of

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accorda ...

, and thus most research efforts focus on some variety of

rocket propulsion A rocket (from it, rocchetto, , bobbin/spool) 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. Rocket engines work entirely fr ...

, such as chemical, nuclear or electric. * Spacecraft design – a specialized form of systems engineering that centers on combining all the necessary subsystems for a particular

launch vehicle A launch vehicle or carrier rocket is a rocket designed to carry a payload ( spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pads, supported by a launch control center and ...

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioi ...

. * Controls – keeping a satellite or rocket in its desired orbit (as in spacecraft navigation) and orientation (as in

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

). * Space environment – although more a sub-discipline of

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

rather than astronautics, the effects of

space weather Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the time varying conditions within the Solar System, including the solar wind, emphasizing the space surrounding the Earth, including conditions in the ...

and other environmental issues constitute an increasingly important field of study for spacecraft designers. * Bioastronautics

Related fields of study

* Aeronautics and

Mechanical engineering Mechanical engineering is the study of physical machines that may involve force and movement. It is an engineering branch that combines engineering physics and mathematics principles with materials science, to design, analyze, manufacture, an ...

Physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

History

Subdisciplines

Related fields of study

See also

References

Further reading