Astronautics
Encyclopedia
Astronautics, and related astronautical engineering, is the theory and practice of navigation beyond the Earth's atmosphere
. In other words, it is the science and technology of space flight.
The term astronautics was coined by analogy with aeronautics
. As there is a certain degree of technology overlapping between the two fields, the term aerospace
is often used to describe them both.
As with aeronautics, the restrictions of mass, temperatures, and external forces require that applications in space survive extreme conditions: high-grade vacuum
, the radiation
bombardment of interplanetary space, the magnetic belts of low Earth orbit
. Space launch vehicles
must withstand titanic forces, while satellites can experience huge variations in temperature in very brief periods. 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 his 1687 treatise Philosophiae Naturalis Principia Mathematica
. Other mathematicians, such as Swiss Leonhard Euler
and Italian Joseph Louis Lagrange
also made essential contributions in the 18th and 19th centuries. In spite of this, Astronautics did not become a practical discipline until the mid-20th century. On the other hand, the question of space flight tickled the literary imaginations of such figures as Jules Verne
and HG Wells.
At the beginning of the 20th century, Russian Konstantin Tsiolkovsky
derived the famous rocket equation, the governing equation
for a rocket-based propulsion
. This equation makes it possible to compute the final velocity of a rocket from the mass of spacecraft(
), combined mass of propellant and spacecraft (
) and exhaust velocity of the propellant (
).
For more information on the mathematical basis of space travel, see space mathematics
.
By the early 1920s, the American
Robert Goddard was developing liquid-fueled rocket
s, which would in a few brief decades become a critical component in the designs of such famous rockets as the V-2
and Saturn V
.
Earth's atmosphere
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...
. In other words, it is the science and technology of space flight.
The term astronautics was coined by analogy with aeronautics
Aeronautics
Aeronautics is the science involved with the study, design, and manufacturing of airflight-capable machines, or the techniques of operating aircraft and rocketry within the atmosphere...
. As there is a certain degree of technology overlapping between the two fields, the term aerospace
Aerospace
Aerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space...
is often used to describe them both.
As with aeronautics, the restrictions of mass, temperatures, and external forces require that applications in space survive extreme conditions: high-grade vacuum
Vacuum
In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
, the radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
bombardment of interplanetary space, the magnetic belts of low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...
. Space launch vehicles
Launch vehicle
In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure....
must withstand titanic forces, while satellites can experience huge variations in temperature in very brief periods. 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
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...
.
History
The early history of astronautics is theoretical: the fundamental mathematics of space travel was established by Isaac NewtonIsaac Newton
Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...
in his 1687 treatise Philosophiae Naturalis Principia Mathematica
Philosophiae Naturalis Principia Mathematica
Philosophiæ Naturalis Principia Mathematica, Latin for "Mathematical Principles of Natural Philosophy", often referred to as simply the Principia, is a work in three books by Sir Isaac Newton, first published 5 July 1687. Newton also published two further editions, in 1713 and 1726...
. Other mathematicians, such as Swiss Leonhard Euler
Leonhard Euler
Leonhard Euler was a pioneering Swiss mathematician and physicist. He made important discoveries in fields as diverse as infinitesimal calculus and graph theory. He also introduced much of the modern mathematical terminology and notation, particularly for mathematical analysis, such as the notion...
and Italian Joseph Louis Lagrange
Joseph Louis Lagrange
Joseph-Louis Lagrange , born Giuseppe Lodovico Lagrangia, was a mathematician and astronomer, who was born in Turin, Piedmont, lived part of his life in Prussia and part in France, making significant contributions to all fields of analysis, to number theory, and to classical and celestial mechanics...
also made essential contributions in the 18th and 19th centuries. In spite of this, Astronautics did not become a practical discipline until the mid-20th century. On the other hand, the question of space flight tickled the literary imaginations of such figures as Jules Verne
Jules Verne
Jules Gabriel Verne was a French author who pioneered the science fiction genre. He is best known for his novels Twenty Thousand Leagues Under the Sea , A Journey to the Center of the Earth , and Around the World in Eighty Days...
and HG Wells.
At the beginning of the 20th century, Russian Konstantin Tsiolkovsky
Konstantin Tsiolkovsky
Konstantin Eduardovich Tsiolkovsky was an Imperial Russian and Soviet rocket scientist and pioneer of the astronautic theory. Along with his followers the German Hermann Oberth and the American Robert H. Goddard, he is considered to be one of the founding fathers of rocketry and astronautics...
derived the famous rocket equation, the governing equation
Equation
An equation is a mathematical statement that asserts the equality of two expressions. In modern notation, this is written by placing the expressions on either side of an equals sign , for examplex + 3 = 5\,asserts that x+3 is equal to 5...
for a rocket-based propulsion
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
. This equation makes it possible to compute the final velocity of a rocket from the mass of spacecraft(
), combined mass of propellant and spacecraft () and exhaust velocity of the propellant ().For more information on the mathematical basis of space travel, see space mathematics
Space mathematics
Space mathematics may refer to:* Orbital mechanics* Newton's laws of motion* Newton's law of universal gravitation* Space...
.
By the early 1920s, the American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
Robert Goddard was developing liquid-fueled rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
s, which would in a few brief decades become a critical component in the designs of such famous rockets as the V-2
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range combat-ballistic missile and first known...
and Saturn V
Saturn V
The Saturn V was an American human-rated expendable rocket used by NASA's Apollo and Skylab programs from 1967 until 1973. A multistage liquid-fueled launch vehicle, NASA launched 13 Saturn Vs from the Kennedy Space Center, Florida with no loss of crew or payload...
.
Sub-disciplines
Although many regard Astronautics itself as a rather specialized subject, engineers and scientists working in this area must be knowledgeable about many distinct fields of knowledge.- AstrodynamicsAstrodynamicsOrbital 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 motion and Newton's law of universal gravitation. It...
: the study of orbital motion. Those specializing in this field examine topics such as spacecraft trajectories, ballistics and celestial mechanics. - Spacecraft propulsionSpacecraft propulsionSpacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. There are many different methods. Each method has drawbacks and advantages, and spacecraft propulsion is an active area of research. However, most spacecraft today are propelled by forcing a gas from the...
: how spacecraft change orbits, and how they are launchedRocket launchA rocket launch is the takeoff phase of the flight of a rocket. Launches for orbital spaceflights, or launches into interplanetary space, are usually from a fixed location on the ground, but may also be from a floating platform such as the San Marco platform, or the Sea Launch launch...
. Most spacecraft have some variety of rocket engineRocket engineA rocket engine, or simply "rocket", is a jet engineRocket Propulsion Elements; 7th edition- chapter 1 that uses only propellant mass for forming its high speed propulsive jet. Rocket engines are reaction engines and obtain thrust in accordance with Newton's third law...
, and thus most researchResearchResearch can be defined as the scientific search for knowledge, or as any systematic investigation, to establish novel facts, solve new or existing problems, prove new ideas, or develop new theories, usually using a scientific method...
efforts focus on some variety of rocket propulsionRocketA rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
, such as chemical, nuclear propulsionNuclear propulsionNuclear propulsion includes a wide variety of propulsion methods that fulfil the promise of the Atomic Age by using some form of nuclear reaction as their primary power source.- Surface ships and submarines :...
, or electric propulsion. - Spacecraft designSpacecraft design- Origin :Spacecraft design was born as a discipline in the 50s and 60s with the advent of American and Russian space exploration programs. Since then it has progressed, although typically less than comparable terrestrial technologies. This is for a large part due to the challenging space...
: a specialized form of systems engineeringSystems engineeringSystems engineering is an interdisciplinary field of engineering that focuses on how complex engineering projects should be designed and managed over the life cycle of the project. Issues such as logistics, the coordination of different teams, and automatic control of machinery become more...
which centers on combining all the necessary sub-systems for a particular launch vehicleLaunch vehicleIn spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure....
or satelliteSatelliteIn the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon.... - ControlsControl engineeringControl engineering or Control systems engineering is the engineering discipline that applies control theory to design systems with predictable behaviors...
: keeping a satellite or rocket in its desired orbit (as in spacecraft navigation) and orientation (as in attitude control). - Space environmentSpace environmentSpace environment is a branch of astronautics, aerospace engineering and space physics that seeks to understand and address conditions existing in space that affect the operation of spacecraft...
: although more a sub-discipline of PhysicsPhysicsPhysics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
rather than Astronautics, the effects of space weatherSpace weatherSpace weather is the concept of changing environmental conditions in near-Earth space or thespace from the Sun's atmosphere to the Earth's atmosphere. It is distinct from the concept ofweather within the Earth's planetary atmosphere...
and other environmental issues constitute an increasingly important field of study for spacecraft designers.
Related fields of study
- AeronauticsAeronauticsAeronautics is the science involved with the study, design, and manufacturing of airflight-capable machines, or the techniques of operating aircraft and rocketry within the atmosphere...
and aerospaceAerospaceAerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space... - Mechanical engineeringMechanical engineeringMechanical engineering is a discipline of engineering that applies the principles of physics and materials science for analysis, design, manufacturing, and maintenance of mechanical systems. It is the branch of engineering that involves the production and usage of heat and mechanical power for the...
- PhysicsPhysicsPhysics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
See also
- AerospaceAerospaceAerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space...
- Atmospheric reentryAtmospheric reentryAtmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...
- Konstantin TsiolkovskyKonstantin TsiolkovskyKonstantin Eduardovich Tsiolkovsky was an Imperial Russian and Soviet rocket scientist and pioneer of the astronautic theory. Along with his followers the German Hermann Oberth and the American Robert H. Goddard, he is considered to be one of the founding fathers of rocketry and astronautics...
- Space RaceSpace RaceThe Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
- Robert GoddardRobert H. GoddardRobert Hutchings Goddard was an American professor, physicist and inventor who is credited with creating and building the world's first liquid-fueled rocket, which he successfully launched on March 16, 1926...
- Wernher von BraunWernher von BraunWernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
- SpacefaringSpacefaringTo be spacefaring is to be capable of and active in the art of space travel or space transport, the operation of spacecraft or spaceplanes. It involves a knowledge of a variety of topics and development of specialised skills including : aeronautics; astronautics; programs to train astronauts; space...
- Frank MalinaFrank MalinaFrank Joseph Malina was an American aeronautical engineer and painter, especially known for becoming both a pioneer in the art world and the realm of scientific engineering.-Early life:...