349 relations: Absorption (electromagnetic radiation), Acceleration, Active galactic nucleus, Aether (classical element), Age of the universe, Air embolism, Albert Einstein, Alexander von Humboldt, Alpha Centauri, Ancient Greece, Andromeda Galaxy, Annual Review of Astronomy and Astrophysics, Anti-satellite weapon, Antimatter, Apollo 8, Apsis, Arabidopsis thaliana, Arc welding, Aristotle, Armstrong limit, Arthur Eddington, Asteroid mining, Astronaut, Astronomer, Astronomical object, Astronomical radio source, Astronomical unit, Astronomy, Astrophysical jet, Atmosphere, Atmosphere of Earth, Atmospheric entry, Atmospheric pressure, Atomic nucleus, Aurora, Bacillus subtilis, Balloon (aeronautics), Barometer, Barotrauma, Baryon, Beam-powered propulsion, Big Bang, BIOPAN, Black body, Black hole, Blaise Pascal, Bogotá, Bow shocks in astrophysics, Brazil, Bussard ramjet, ..., Cancer, Carbon monoxide, Centrifugal force, Centripetal force, Cepheid variable, Charles Édouard Guillaume, Circulatory system, Colombia, Communications satellite, Constellation, Corona, Cosmic background radiation, Cosmic dust, Cosmic microwave background, Cosmic neutrino background, Cosmic ray, Cosmology, Cubic metre, Daedalus (crater), Dark energy, Dark matter, Decompression sickness, Democratic Republic of the Congo, Density, Deuterium, Donald Pettit, Drag (physics), Dynamic pressure, Dynamo, Earth, Earth's magnetic field, Ebullism, Ecuador, Edwin Hubble, Electromagnetic interference, Electromagnetic radiation, Electromagnetic spectrum, Electromagnetism, Electron, Electronvolt, Elliptical galaxy, Emmeline Charlotte Elizabeth Stuart-Wortley, Erich Regener, Escape velocity, Evangelista Torricelli, Expansion of the universe, Explorer II, Extinction (astronomy), Far side of the Moon, Fédération Aéronautique Internationale, Flatness (cosmology), Frame of reference, Frank Borman, Friction, Friedrich Bessel, Galaxy, Galaxy filament, Galaxy groups and clusters, Galileo Galilei, Gastrointestinal tract, Gauss (unit), Geocentric orbit, Geomagnetic pole, Geomagnetic storm, Georges Lemaître, Giordano Bruno, Global Positioning System, Gravity, Gravity of Earth, H. G. Wells, Harry George Armstrong, Health threat from cosmic rays, Heber Doust Curtis, Heliocentrism, Heliophysics, Heliosphere, Helium, Helium-3, Henrietta Swan Leavitt, Hill sphere, History of China, Horror vacui (physics), Hubble Space Telescope, Hubble's law, Human body temperature, Human evolution, Human eye, Human skeleton, Hydrogen, Hydrogen atom, Hypoxia (medical), Immune system, Indonesia, Infrared telescope, International Union of Pure and Applied Chemistry, Interplanetary dust cloud, Interstellar Boundary Explorer, Interstellar medium, Interstellar travel, Ion, Ionosphere, ITU-R, Jim Lovell, John Milton, Joule, Kármán line, Kenya, Kinetic theory of gases, Lagrangian point, Lethargy, Lift (force), Light-year, List of government space agencies, List of interstellar and circumstellar molecules, List of topics in space, Local Bubble, Local Group, Location of Earth, Low Earth orbit, Luminiferous aether, Luna 1, Lunar distance (astronomy), Lung, Mach number, Magnetic field, Magnetohydrodynamics, Magnetopause, Magnetosphere, Mariner 2, Mariner 4, Mars, Mass–energy equivalence, Matter, Mean free path, Meteoroid, Michelson–Morley experiment, Micro-g environment, Micrometre, Microorganism, Milky Way, Minor planet, Minute and second of arc, Molecular cloud, Molecule, Momentum exchange tether, Monthly Notices of the Royal Astronomical Society, Moon, Moon Treaty, Muscle atrophy, NASA, Natural satellite, Nausea, Nebular hypothesis, Nervous system, Neutrino, Nicholas of Cusa, Nicotiana tabacum, Non-rocket spacelaunch, North American X-15, Nova, Nuclear fusion, Nuclear weapon, Null result, Number density, Observable universe, Ontology, Ophiuchus, Orbit, Orbit of the Moon, Orbital speed, Order of magnitude, Organic chemistry, Orion Arm, Otto von Guericke, Outer space, Outer Space Treaty, Outline of space science, Outline of space technology, Oxygen, Panspermia, Paradise Lost, Parmenides, Parsec, Partial pressure, Pascal (unit), Peculiar velocity, Perturbation (astronomy), Photon, Physiology, Planet, Planetary nebula, Plasma (physics), Polarization (waves), Polarization in astronomy, Pressure, Pressure suit, Project Daedalus, Proton, Puy de Dôme, R-7 Semyorka, Radiation, Radiation pressure, Radio astronomy, Radio galaxy, Radio telescope, Ralph Asher Alpher, Rarefaction, Recombination (cosmology), Reconnaissance satellite, Red blood cell, Redshift, Relativistic speed, Remote sensing, René Descartes, Republic of the Congo, Risk factor, Robert Herman, Rocket launch, Rotational spectroscopy, Satellite, Satellite navigation, Scattering, Shape of the universe, Shock wave, Solar sail, Solar System, Solar wind, Sovereignty, Space adaptation syndrome, Space and survival, Space debris, Space elevator, Space exploration, Space law, Space manufacturing, Space Race, Space station, Space weather, Spacecraft, Spaceflight, Spaceflight osteopenia, Special relativity, Speed of light, Sputnik 1, Standard conditions for temperature and pressure, Star, Star system, Stellar nucleosynthesis, Stellar parallax, Stellar wind, Stellar-wind bubble, Sub-orbital spaceflight, Subatomic particle, Sun, Supernova, Taurus (constellation), Temperature, Theodore von Kármán, Thermodynamic equilibrium, Thermosphere, Thomas Digges, Three-dimensional space, Timeline of knowledge about the interstellar and intergalactic medium, Timeline of Solar System exploration, Timeline of spaceflight, Trihydrogen cation, Uganda, Ultra-high-energy cosmic ray, Unified atomic mass unit, United Nations Committee on the Peaceful Uses of Outer Space, United Nations General Assembly, United Nations resolution, Universe, Unmanned spacecraft, V-2 rocket, Vacuum, Vacuum energy, Van Allen radiation belt, Vapour pressure of water, Venera 1, Venus, Vertigo, Void (astronomy), Vomiting, Vostok 1, Voyager 1, Voyager program, Warm–hot intergalactic medium, Weather satellite, Western culture, Westphalian sovereignty, White blood cell, Wilkinson Microwave Anisotropy Probe, William Anders, William Gilbert (astronomer), Yuri Gagarin, Zhang Heng, Zodiacal light, 61 Cygni. 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In physics, absorption of electromagnetic radiation is the way in which the energy of a photon is taken up by matter, typically the electrons of an atom.
In physics, acceleration is the rate of change of velocity of an object with respect to time.
An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much higher than normal luminosity over at least some portion—and possibly all—of the electromagnetic spectrum, with characteristics indicating that the excess luminosity is not produced by stars.
According to ancient and medieval science, aether (αἰθήρ aithēr), also spelled æther or ether and also called quintessence, is the material that fills the region of the universe above the terrestrial sphere.
In physical cosmology, the age of the universe is the time elapsed since the Big Bang.
An air embolism, also known as a gas embolism, is a blood vessel blockage caused by one or more bubbles of air or other gas in the circulatory system.
Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist who developed the theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics).
Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 17696 May 1859) was a Prussian polymath, geographer, naturalist, explorer, and influential proponent of Romantic philosophy and science.
Alpha Centauri (α Centauri, abbreviated Alf Cen or α Cen) is the star system closest to the Solar System, being from the Sun.
Ancient Greece was a civilization belonging to a period of Greek history from the Greek Dark Ages of the 13th–9th centuries BC to the end of antiquity (AD 600).
The Andromeda Galaxy, also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth, and the nearest major galaxy to the Milky Way.
The Annual Review of Astronomy and Astrophysics is an annual peer reviewed scientific journal published by Annual Reviews.
Anti-satellite weapons (ASAT) are space weapons designed to incapacitate or destroy satellites for strategic military purposes.
In modern physics, antimatter is defined as a material composed of the antiparticle (or "partners") to the corresponding particles of ordinary matter.
Apollo 8, the second manned spaceflight mission in the United States Apollo space program, was launched on December 21, 1968, and became the first manned spacecraft to leave Earth orbit, reach the Earth's Moon, orbit it and return safely to Earth.
An apsis (ἁψίς; plural apsides, Greek: ἁψῖδες) is an extreme point in the orbit of an object.
Arabidopsis thaliana, the thale cress, mouse-ear cress or arabidopsis, is a small flowering plant native to Eurasia and Africa.
Arc welding is a process that is used to join metal to metal by using electricity to create enough heat to melt metal, and the melted metals when cool result in a binding of the metals.
Aristotle (Ἀριστοτέλης Aristotélēs,; 384–322 BC) was an ancient Greek philosopher and scientist born in the city of Stagira, Chalkidiki, in the north of Classical Greece.
The Armstrong limit or Armstrong's line is a measure of altitude above which atmospheric pressure is sufficiently low that water boils at the normal temperature of the human body.
Sir Arthur Stanley Eddington (28 December 1882 – 22 November 1944) was an English astronomer, physicist, and mathematician of the early 20th century who did his greatest work in astrophysics.
Asteroid mining is the exploitation of raw materials from asteroids and other minor planets, including near-Earth objects.
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft.
An astronomer is a scientist in the field of astronomy who concentrates their studies on a specific question or field outside the scope of Earth.
An astronomical object or celestial object is a naturally occurring physical entity, association, or structure that exists in the observable universe.
Astronomical radio sources are objects in outer space that emit strong radio waves.
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
Astronomy (from ἀστρονομία) is a natural science that studies celestial objects and phenomena.
An astrophysical jet is an astronomical phenomenon where outflows of ionised matter are emitted as an extended beam along the axis of rotation.
An atmosphere is a layer or a set of layers of gases surrounding a planet or other material body, that is held in place by the gravity of that body.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet or natural satellite.
Atmospheric pressure, sometimes also called barometric pressure, is the pressure within the atmosphere of Earth (or that of another planet).
The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.
An aurora (plural: auroras or aurorae), sometimes referred to as polar lights, northern lights (aurora borealis) or southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in the high-latitude regions (around the Arctic and Antarctic).
Bacillus subtilis, known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium, found in soil and the gastrointestinal tract of ruminants and humans.
In aeronautics, a balloon is an unpowered aerostat, which remains aloft or floats due to its buoyancy.
A barometer is a scientific instrument used in meteorology to measure atmospheric pressure.
Barotrauma is physical damage to body tissues caused by a difference in pressure between a gas space inside, or in contact with the body, and the surrounding gas or fluid.
A baryon is a composite subatomic particle made up of three quarks (a triquark, as distinct from mesons, which are composed of one quark and one antiquark).
Beam-powered propulsion, also known as directed energy propulsion, is a class of aircraft or spacecraft propulsion that uses energy beamed to the spacecraft from a remote power plant to provide energy.
The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution.
BIOPAN is a multi-user research program by the European Space Agency (ESA) designed to investigate the effect of the space environment on biological material.
A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence.
A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it.
Blaise Pascal (19 June 1623 – 19 August 1662) was a French mathematician, physicist, inventor, writer and Catholic theologian.
Bogotá, officially Bogotá, Distrito Capital, abbreviated Bogotá, D.C., and formerly known as Santafé de Bogotá between 1991 and 2000, is the capital and largest city of Colombia, administered as the Capital District, although often thought of as part of Cundinamarca.
Bow shocks form the boundary between a magnetosphere and an ambient magnetized medium.
Brazil (Brasil), officially the Federative Republic of Brazil (República Federativa do Brasil), is the largest country in both South America and Latin America.
The Bussard ramjet is a theoretical method of spacecraft propulsion proposed in 1960 by the physicist Robert W. Bussard, popularized by Poul Anderson's novel Tau Zero, Larry Niven in his Known Space series of books, Vernor Vinge in his Zones of Thought series, and referred to by Carl Sagan in the television series and book Cosmos.
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.
Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air.
In Newtonian mechanics, the centrifugal force is an inertial force (also called a "fictitious" or "pseudo" force) directed away from the axis of rotation that appears to act on all objects when viewed in a rotating frame of reference.
A centripetal force (from Latin centrum, "center" and petere, "to seek") is a force that makes a body follow a curved path.
A Cepheid variable is a type of star that pulsates radially, varying in both diameter and temperature and producing changes in brightness with a well-defined stable period and amplitude.
Charles Édouard Guillaume (15 February 1861, Fleurier, Switzerland – 13 May 1938, Sèvres, France) was a Swiss physicist who received the Nobel Prize in Physics in 1920 in recognition of the service he had rendered to precision measurements in physics by his discovery of anomalies in nickel steel alloys.
The circulatory system, also called the cardiovascular system or the vascular system, is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment and help in fighting diseases, stabilize temperature and pH, and maintain homeostasis.
Colombia, officially the Republic of Colombia, is a sovereign state largely situated in the northwest of South America, with territories in Central America.
A communications satellite is an artificial satellite that relays and amplifies radio telecommunications signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth.
A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.
A corona (Latin, 'crown') is an aura of plasma that surrounds the Sun and other stars.
Cosmic background radiation is electromagnetic radiation from the big bang.
Cosmic dust, also called extraterrestrial dust or space dust, is dust which exists in outer space, as well as all over planet Earth.
The cosmic microwave background (CMB, CMBR) is electromagnetic radiation as a remnant from an early stage of the universe in Big Bang cosmology.
The cosmic neutrino background (CNB, CνB) is the universe's background particle radiation composed of neutrinos.
Cosmic rays are high-energy radiation, mainly originating outside the Solar System and even from distant galaxies.
Cosmology (from the Greek κόσμος, kosmos "world" and -λογία, -logia "study of") is the study of the origin, evolution, and eventual fate of the universe.
The cubic metre (in British English and international spelling as used by the International Bureau of Weights and Measures) or cubic meter (in American English) is the SI derived unit of volume.
Daedalus is a prominent crater located near the center of the far side of the Moon.
In physical cosmology and astronomy, dark energy is an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe.
Dark matter is a theorized form of matter that is thought to account for approximately 80% of the matter in the universe, and about a quarter of its total energy density.
Decompression sickness (DCS; also known as divers' disease, the bends, aerobullosis, or caisson disease) describes a condition arising from dissolved gases coming out of solution into bubbles inside the body on depressurisation.
The Democratic Republic of the Congo (République démocratique du Congo), also known as DR Congo, the DRC, Congo-Kinshasa or simply the Congo, is a country located in Central Africa.
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume.
Deuterium (or hydrogen-2, symbol or, also known as heavy hydrogen) is one of two stable isotopes of hydrogen (the other being protium, or hydrogen-1).
Donald Roy Pettit (born April 20, 1955) is an American chemical engineer and a NASA astronaut.
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid.
Dynamic pressure (sometimes called velocity pressure) is the increase in a moving fluid's pressure over its static value due to motion.
A dynamo is an electrical generator that creates direct current using a commutator.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from the Earth's interior out into space, where it meets the solar wind, a stream of charged particles emanating from the Sun.
Ebullism is the formation of gas bubbles in bodily fluids due to reduced environmental pressure, for example at high altitude.
Ecuador (Ikwadur), officially the Republic of Ecuador (República del Ecuador, which literally translates as "Republic of the Equator"; Ikwadur Ripuwlika), is a representative democratic republic in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean to the west.
Edwin Powell Hubble (November 20, 1889 – September 28, 1953) was an American astronomer.
Electromagnetic interference (EMI), also called radio-frequency interference (RFI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.
In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.
The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies.
Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles.
The electron is a subatomic particle, symbol or, whose electric charge is negative one elementary charge.
In physics, the electronvolt (symbol eV, also written electron-volt and electron volt) is a unit of energy equal to approximately joules (symbol J).
An elliptical galaxy is a type of galaxy having an approximately ellipsoidal shape and a smooth, nearly featureless image.
Lady Emmeline Stuart-Wortley née Manners (1806 – 20 October 1855) was an English poet and writer, best known for her Travels in the United States, etc.
Erich Rudolf Alexander Regener (12 November 1881 – 27 February 1955) was a German physicist known primarily for the design and construction of instruments to measure cosmic ray intensity at various altitudes.
In physics, escape velocity is the minimum speed needed for an object to escape from the gravitational influence of a massive body.
Evangelista Torricelli; 15 October 1608 – 25 October 1647) was an Italian physicist and mathematician, best known for his invention of the barometer, but is also known for his advances in optics and work on the method of indivisibles.
The expansion of the universe is the increase of the distance between two distant parts of the universe with time.
Explorer II was a manned U.S. high-altitude balloon that was launched on November 11, 1935 and reached a record altitude of.
In astronomy, extinction is the absorption and scattering of electromagnetic radiation by dust and gas between an emitting astronomical object and the observer.
The far side of the Moon (sometimes figuratively known as the dark side of the Moon) is the hemisphere of the Moon that always faces away from Earth.
The Fédération aéronautique internationale (FAI; The World Air Sports Federation), is the world governing body for air sports.
The concept of "curvature of space" is fundamental to cosmology.
In physics, a frame of reference (or reference frame) consists of an abstract coordinate system and the set of physical reference points that uniquely fix (locate and orient) the coordinate system and standardize measurements.
Frank Frederick Borman II (born March 14, 1928), (Col, USAF, Ret.), is a retired United States Air Force pilot, aeronautical engineer, test pilot, and NASA astronaut, best remembered as the Commander of Apollo 8, the first mission to fly around the Moon, making him, along with crew mates Jim Lovell and Bill Anders, the first of only 24 humans to do so.
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
Friedrich Wilhelm Bessel (22 July 1784 – 17 March 1846) was a German astronomer, mathematician, physicist and geodesist.
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.
The distribution reveals fine, filamentary structures.
Galaxy groups and clusters are the largest known gravitationally bound objects to have arisen thus far in the process of cosmic structure formation.
Galileo Galilei (15 February 1564Drake (1978, p. 1). The date of Galileo's birth is given according to the Julian calendar, which was then in force throughout Christendom. In 1582 it was replaced in Italy and several other Catholic countries with the Gregorian calendar. Unless otherwise indicated, dates in this article are given according to the Gregorian calendar. – 8 January 1642) was an Italian polymath.
The gastrointestinal tract (digestive tract, digestional tract, GI tract, GIT, gut, or alimentary canal) is an organ system within humans and other animals which takes in food, digests it to extract and absorb energy and nutrients, and expels the remaining waste as feces.
The gauss, abbreviated as G or Gs, is the cgs unit of measurement of magnetic flux density (or "magnetic induction") (B).
A geocentric orbit or Earth orbit involves any object orbiting Planet Earth, such as the Moon or artificial satellites.
The geomagnetic poles are antipodal points where the axis of a best-fitting dipole intersects the Earth's surface.
A geomagnetic storm (commonly referred to as a solar storm) is a temporary disturbance of the Earth's magnetosphere caused by a solar wind shock wave and/or cloud of magnetic field that interacts with the Earth's magnetic field.
Georges Henri Joseph Édouard Lemaître, RAS Associate (17 July 1894 – 20 June 1966) was a Belgian Catholic Priest, astronomer and professor of physics at the Catholic University of Leuven.
Giordano Bruno (Iordanus Brunus Nolanus; 1548 – 17 February 1600), born Filippo Bruno, was an Italian Dominican friar, philosopher, mathematician, poet, and cosmological theorist.
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Air Force.
Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward (or gravitate toward) one another.
The gravity of Earth, which is denoted by, refers to the acceleration that is imparted to objects due to the distribution of mass within Earth.
Herbert George Wells.
Harry George Armstrong (February 17, 1899 – February 5, 1983) was a Major General in the United States Air Force, a physician, and an airman.
The health threat from cosmic rays is the danger posed by galactic cosmic rays (GCR) and solar energetic particles to astronauts on interplanetary missions or any missions that venture through the Van-Allen Belts or outside the Earth's magnetosphere.
Heber Doust Curtis (June 27, 1872 – January 9, 1942) was an American astronomer.
Heliocentrism is the astronomical model in which the Earth and planets revolve around the Sun at the center of the Solar System.
The term heliophysics means "physics of the Sun" (the prefix "helio", from Attic Greek hḗlios, means Sun), and appears to have been used only in that sense until quite recently.
The heliosphere is the bubble-like region of space dominated by the Sun, which extends far beyond the orbit of Pluto.
Helium (from lit) is a chemical element with symbol He and atomic number 2.
Helium-3 (He-3, also written as 3He, see also helion) is a light, non-radioactive isotope of helium with two protons and one neutron (common helium having two protons and two neutrons).
Henrietta Swan Leavitt (July 4, 1868 – December 12, 1921) was an American astronomer who discovered the relation between the luminosity and the period of Cepheid variable stars.
An astronomical body's Hill sphere is the region in which it dominates the attraction of satellites.
The earliest known written records of the history of China date from as early as 1250 BC,William G. Boltz, Early Chinese Writing, World Archaeology, Vol.
In physics, horror vacui, or plenism, is commonly stated as "Nature abhors a vacuum".
The Hubble Space Telescope (HST) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation.
Hubble's law is the name for the observation in physical cosmology that.
Normal human body temperature, also known as normothermia or euthermia, is the typical temperature range found in humans.
Human evolution is the evolutionary process that led to the emergence of anatomically modern humans, beginning with the evolutionary history of primates – in particular genus Homo – and leading to the emergence of Homo sapiens as a distinct species of the hominid family, the great apes.
The human eye is an organ which reacts to light and pressure.
The human skeleton is the internal framework of the body.
Hydrogen is a chemical element with symbol H and atomic number 1.
A hydrogen atom is an atom of the chemical element hydrogen.
Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level.
The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease.
Indonesia (or; Indonesian), officially the Republic of Indonesia (Republik Indonesia), is a transcontinental unitary sovereign state located mainly in Southeast Asia, with some territories in Oceania.
An infrared telescope is a telescope that uses infrared light to detect celestial bodies.
The International Union of Pure and Applied Chemistry (IUPAC) is an international federation of National Adhering Organizations that represents chemists in individual countries.
The interplanetary dust cloud, or zodiacal cloud, consists of cosmic dust (small particles floating in outer space) that pervades the space between planets in the Solar System and other planetary systems.
Interstellar Boundary Explorer (IBEX) is a NASA satellite that is making a map of the boundary between the Solar System and interstellar space.
In astronomy, the interstellar medium (ISM) is the matter and radiation that exists in the space between the star systems in a galaxy.
Interstellar travel is the term used for hypothetical crewed or uncrewed travel between stars or planetary systems.
An ion is an atom or molecule that has a non-zero net electrical charge (its total number of electrons is not equal to its total number of protons).
The ionosphere is the ionized part of Earth's upper atmosphere, from about to altitude, a region that includes the thermosphere and parts of the mesosphere and exosphere.
The ITU Radiocommunication Sector (ITU-R) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU) and is responsible for radio communication.
James Arthur Lovell Jr. (born March 25, 1928) is a former NASA astronaut, Naval Aviator, and retired Navy captain.
John Milton (9 December 16088 November 1674) was an English poet, polemicist, man of letters, and civil servant for the Commonwealth of England under its Council of State and later under Oliver Cromwell.
The joule (symbol: J) is a derived unit of energy in the International System of Units.
The Kármán line, or Karman line, lies at an altitude of above Earth's sea level and commonly represents the boundary between Earth's atmosphere and outer space.
Kenya, officially the Republic of Kenya, is a country in Africa with its capital and largest city in Nairobi.
The kinetic theory describes a gas as a large number of submicroscopic particles (atoms or molecules), all of which are in constant rapid motion that has randomness arising from their many collisions with each other and with the walls of the container.
In celestial mechanics, the Lagrangian points (also Lagrange points, L-points, or libration points) are positions in an orbital configuration of two large bodies, wherein a small object, affected only by the gravitational forces from the two larger objects, will maintain its position relative to them.
Lethargy is a state of tiredness, weariness, fatigue, or lack of energy.
A fluid flowing past the surface of a body exerts a force on it.
The light-year is a unit of length used to express astronomical distances and measures about 9.5 trillion kilometres or 5.9 trillion miles.
This is a list of government agencies engaged in activities related to outer space and space exploration.
This is a list of molecules that have been detected in the interstellar medium and circumstellar envelopes, grouped by the number of component atoms.
List of Topics in Space; topics as related to outer space.
The Local Bubble, or Local Cavity, is a relative cavity in the interstellar medium (ISM) in the Orion Arm of the Milky Way.
The Local Group is the galaxy group that includes the Milky Way.
Knowledge of the location of Earth has been shaped by 400 years of telescopic observations, and has expanded radically in the last century.
A low Earth orbit (LEO) is an orbit around Earth with an altitude of or less, and with an orbital period of between about 84 and 127 minutes.
In the late 19th century, luminiferous aether or ether ("luminiferous", meaning "light-bearing"), was the postulated medium for the propagation of light.
Luna 1, also known as Mechta (Мечта, lit.: Dream), E-1 No.4 and First Lunar Rover, was the first spacecraft to reach the vicinity of the Earth's Moon, and the first spacecraft to be placed in heliocentric orbit.
Lunar distance (LD or \Delta_), also called Earth–Moon distance, Earth–Moon characteristic distance, or distance to the Moon, is a unit of measure in astronomy.
The lungs are the primary organs of the respiratory system in humans and many other animals including a few fish and some snails.
In fluid dynamics, the Mach number (M or Ma) is a dimensionless quantity representing the ratio of flow velocity past a boundary to the local speed of sound.
A magnetic field is a vector field that describes the magnetic influence of electrical currents and magnetized materials.
Magnetohydrodynamics (MHD; also magneto-fluid dynamics or hydro­magnetics) is the study of the magnetic properties of electrically conducting fluids.
The magnetopause is the abrupt boundary between a magnetosphere and the surrounding plasma.
A magnetosphere is the region of space surrounding an astronomical object in which charged particles are manipulated or affected by that object's magnetic field.
Mariner 2 (Mariner-Venus 1962), an American space probe to Venus, was the first robotic space probe to conduct a successful planetary encounter.
Mariner 4 (together with Mariner 3 known as Mariner–Mars 1964) was the fourth in a series of spacecraft intended for planetary exploration in a flyby mode.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.
In physics, mass–energy equivalence states that anything having mass has an equivalent amount of energy and vice versa, with these fundamental quantities directly relating to one another by Albert Einstein's famous formula: E.
In the classical physics observed in everyday life, matter is any substance that has mass and takes up space by having volume.
In physics, the mean free path is the average distance traveled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions), which modify its direction or energy or other particle properties.
A meteoroid is a small rocky or metallic body in outer space.
The Michelson–Morley experiment was performed between April and July, 1887 by Albert A. Michelson and Edward W. Morley at what is now Case Western Reserve University in Cleveland, Ohio, and published in November of the same year.
The term micro-g environment (also µg, often referred to by the term microgravity) is more or less a synonym for weightlessness and zero-g, but indicates that g-forces are not quite zero—just very small.
The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is an SI derived unit of length equaling (SI standard prefix "micro-".
A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or in a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from 6th century BC India and the 1st century BC book On Agriculture by Marcus Terentius Varro. Microbiology, the scientific study of microorganisms, began with their observation under the microscope in the 1670s by Antonie van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera and anthrax. Microorganisms include all unicellular organisms and so are extremely diverse. Of the three domains of life identified by Carl Woese, all of the Archaea and Bacteria are microorganisms. These were previously grouped together in the two domain system as Prokaryotes, the other being the eukaryotes. The third domain Eukaryota includes all multicellular organisms and many unicellular protists and protozoans. Some protists are related to animals and some to green plants. Many of the multicellular organisms are microscopic, namely micro-animals, some fungi and some algae, but these are not discussed here. They live in almost every habitat from the poles to the equator, deserts, geysers, rocks and the deep sea. Some are adapted to extremes such as very hot or very cold conditions, others to high pressure and a few such as Deinococcus radiodurans to high radiation environments. Microorganisms also make up the microbiota found in and on all multicellular organisms. A December 2017 report stated that 3.45 billion year old Australian rocks once contained microorganisms, the earliest direct evidence of life on Earth. Microbes are important in human culture and health in many ways, serving to ferment foods, treat sewage, produce fuel, enzymes and other bioactive compounds. They are essential tools in biology as model organisms and have been put to use in biological warfare and bioterrorism. They are a vital component of fertile soils. In the human body microorganisms make up the human microbiota including the essential gut flora. They are the pathogens responsible for many infectious diseases and as such are the target of hygiene measures.
The Milky Way is the galaxy that contains our Solar System.
A minor planet is an astronomical object in direct orbit around the Sun (or more broadly, any star with a planetary system) that is neither a planet nor exclusively classified as a comet.
A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.
A molecular cloud, sometimes called a stellar nursery (if star formation is occurring within), is a type of interstellar cloud, the density and size of which permit the formation of molecules, most commonly molecular hydrogen (H2).
A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.
A momentum exchange tether is a kind of space tether that could theorically be used as a launch system, or to change spacecraft orbits.
Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.
The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.
The Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, better known as the Moon Treaty or Moon Agreement, is a multilateral treaty that turns jurisdiction of all celestial bodies (including the orbits around such bodies) over to the international community.
Muscle atrophy is defined as a decrease in the mass of the muscle; it can be a partial or complete wasting away of muscle, and is most commonly experienced when persons suffer temporary disabling circumstances such as being restricted in movement and/or confined to bed as when hospitalized.
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
A natural satellite or moon is, in the most common usage, an astronomical body that orbits a planet or minor planet (or sometimes another small Solar System body).
Nausea or queasiness is an unpleasant sense of unease, discomfort, and revulsion towards food.
The nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System (as well as other planetary systems).
The nervous system is the part of an animal that coordinates its actions by transmitting signals to and from different parts of its body.
A neutrino (denoted by the Greek letter ν) is a fermion (an elementary particle with half-integer spin) that interacts only via the weak subatomic force and gravity.
Nicholas of Cusa (1401 – 11 August 1464), also referred to as Nicholas of Kues and Nicolaus Cusanus, was a German philosopher, theologian, jurist, and astronomer.
Nicotiana tabacum, or cultivated tobacco, is an annually-grown herbaceous plant.
Non-rocket spacelaunch refers to concepts for launch into space where some or all of the needed speed and altitude are provided by something other than rockets, or by other than expendable rockets.
The North American X-15 was a hypersonic rocket-powered aircraft operated by the United States Air Force and the National Aeronautics and Space Administration as part of the X-plane series of experimental aircraft.
A nova (plural novae or novas) or classical nova (CN, plural CNe) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star, that slowly fades over several weeks or many months.
In nuclear physics, nuclear fusion is a reaction in which two or more atomic nuclei come close enough to form one or more different atomic nuclei and subatomic particles (neutrons or protons).
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or from a combination of fission and fusion reactions (thermonuclear bomb).
In science, a null result is a result without the expected content: that is, the proposed result is absent.
In physics, astronomy, chemistry, biology and geography, number density (symbol: n or ρN) is an intensive quantity used to describe the degree of concentration of countable objects (particles, molecules, phonons, cells, galaxies, etc.) in physical space: three-dimensional volumetric number density, two-dimensional areal number density, or one-dimensional line number density.
The observable universe is a spherical region of the Universe comprising all matter that can be observed from Earth at the present time, because electromagnetic radiation from these objects has had time to reach Earth since the beginning of the cosmological expansion.
Ontology (introduced in 1606) is the philosophical study of the nature of being, becoming, existence, or reality, as well as the basic categories of being and their relations.
Ophiuchus is a large constellation straddling the celestial equator.
In physics, an orbit is the gravitationally curved trajectory of an object, such as the trajectory of a planet around a star or a natural satellite around a planet.
The Moon orbits Earth in the prograde direction and completes one revolution relative to the stars in about 27.322 days (a sidereal month) and one revolution relative to the Sun in about 29.530 days (a synodic month).
In gravitationally bound systems, the orbital speed of an astronomical body or object (e.g. planet, moon, artificial satellite, spacecraft, or star) is the speed at which it orbits around either the barycenter or, if the object is much less massive than the largest body in the system, its speed relative to that largest body.
An order of magnitude is an approximate measure of the number of digits that a number has in the commonly-used base-ten number system.
Organic chemistry is a chemistry subdiscipline involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.
The Orion Arm is a minor spiral arm of the Milky Way some across and approximately in length, containing the Solar System, including the Earth.
Otto von Guericke (originally spelled Gericke,; November 20, 1602 – May 11, 1686 (Julian calendar); November 30, 1602 – May 21, 1686 (Gregorian calendar)) was a German scientist, inventor, and politician.
Outer space, or just space, is the expanse that exists beyond the Earth and between celestial bodies.
The Outer Space Treaty, formally the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, is a treaty that forms the basis of international space law.
The following outline is provided as an overview of and topical guide to space science: Space science encompasses all of the scientific disciplines that involve space exploration and study natural phenomena and physical bodies occurring in outer space, such as space medicine and astrobiology.
Space technology is technology developed by space science or the aerospace industry for use in spaceflight, satellites, or space exploration.
Oxygen is a chemical element with symbol O and atomic number 8.
Panspermia is the hypothesis that life exists throughout the Universe, distributed by space dust, meteoroids, asteroids, comets, planetoids, and also by spacecraft carrying unintended contamination by microorganisms.
Paradise Lost is an epic poem in blank verse by the 17th-century English poet John Milton (1608–1674).
Parmenides of Elea (Παρμενίδης ὁ Ἐλεάτης) was a pre-Socratic Greek philosopher from Elea in Magna Graecia (Greater Greece, included Southern Italy).
The parsec (symbol: pc) is a unit of length used to measure large distances to astronomical objects outside the Solar System.
In a mixture of gases, each gas has a partial pressure which is the hypothetical pressure of that gas if it alone occupied the entire volume of the original mixture at the same temperature.
The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
Peculiar motion or peculiar velocity refers to the velocity of an object relative to a rest frame — usually a frame in which the average velocity of some objects is zero.
In astronomy, perturbation is the complex motion of a massive body subject to forces other than the gravitational attraction of a single other massive body.
The photon is a type of elementary particle, the quantum of the electromagnetic field including electromagnetic radiation such as light, and the force carrier for the electromagnetic force (even when static via virtual particles).
Physiology is the scientific study of normal mechanisms, and their interactions, which work within a living system.
A planet is an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.
A planetary nebula, abbreviated as PN or plural PNe, is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives.
Plasma (Henry George Liddell, Robert Scott, A Greek English Lexicon, on Perseus) is one of the four fundamental states of matter, and was first described by chemist Irving Langmuir in the 1920s.
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations.
Polarization is an important phenomenon in astronomy.
Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed.
A pressure suit is a protective suit worn by high-altitude pilots who may fly at altitudes where the air pressure is too low for an unprotected person to survive, even breathing pure oxygen at positive pressure.
Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible unmanned interstellar spacecraft.
Puy de Dôme ((Auvergnat Puèi Domat, Puèi de Doma) is a large lava dome and one of the youngest volcanoes in the Chaîne des Puys region of Massif Central in central France. This chain of volcanoes including numerous cinder cones, lava domes, and maars is far from the edge of any tectonic plate. Puy de Dôme is approximately from Clermont-Ferrand. The Puy-de-Dôme département (with hyphens) is named after the volcano.
The R-7 (Р-7 "Семёрка") was a Soviet missile developed during the Cold War, and the world's first intercontinental ballistic missile.
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
Radiation pressure is the pressure exerted upon any surface due to the exchange of momentum between the object and the electromagnetic field.
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies.
Radio galaxies and their relatives, radio-loud quasars and blazars, are types of active galaxy that are very luminous at radio wavelengths, with luminosities up to 1039 W between 10 MHz and 100 GHz.
A radio telescope is a specialized antenna and radio receiver used to receive radio waves from astronomical radio sources in the sky in radio astronomy.
Ralph Asher Alpher (February 3, 1921 – August 12, 2007) was an American cosmologist, who carried out pioneering work in the early 1950s on the Big Bang model, including big bang nucleosynthesis and predictions of the cosmic microwave background radiation.
Rarefaction is the reduction of an item's density, the opposite of compression.
In cosmology, recombination refers to the epoch at which charged electrons and protons first became bound to form electrically neutral hydrogen atoms.
A reconnaissance satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications.
Red blood cells-- also known as RBCs, red cells, red blood corpuscles, haematids, erythroid cells or erythrocytes (from Greek erythros for "red" and kytos for "hollow vessel", with -cyte translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system.
In physics, redshift happens when light or other electromagnetic radiation from an object is increased in wavelength, or shifted to the red end of the spectrum.
Relativistic speed refers to speed at which relativistic effects become significant to the desired accuracy of measurement of the phenomenon being observed.
Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object and thus in contrast to on-site observation.
René Descartes (Latinized: Renatus Cartesius; adjectival form: "Cartesian"; 31 March 1596 – 11 February 1650) was a French philosopher, mathematician, and scientist.
The Republic of the Congo (République du Congo), also known as the Congo-Brazzaville, the Congo Republic or simply the Congo, is a country in Central Africa.
In epidemiology, a risk factor is a variable associated with an increased risk of disease or infection.
Robert Herman (August 29, 1914 – February 13, 1997) was a United States scientist, best known for his work with Ralph Alpher in 1948-50, on estimating the temperature of cosmic microwave background radiation from the Big Bang explosion.
A rocket launch is the takeoff phase of the flight of a rocket.
Rotational spectroscopy is concerned with the measurement of the energies of transitions between quantized rotational states of molecules in the gas phase.
In the context of spaceflight, a satellite is an artificial object which has been intentionally placed into orbit.
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning.
Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more paths due to localized non-uniformities in the medium through which they pass.
The shape of the universe is the local and global geometry of the universe.
In physics, a shock wave (also spelled shockwave), or shock, is a type of propagating disturbance.
Solar sails (also called light sails or photon sails) are a proposed method of spacecraft propulsion using radiation pressure exerted by sunlight on large mirrors.
The Solar SystemCapitalization of the name varies.
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona.
Sovereignty is the full right and power of a governing body over itself, without any interference from outside sources or bodies.
Space adaptation syndrome (SAS) or space sickness is a condition experienced by around half of space travelers during adaptation to weightlessness.
Space and survival refers to the idea that the long-term survival of the human species and civilization requires proper use of the resources of outer space and the need for space colonization and space science.
Space debris (also known as space junk, space waste, space trash, space litter or space garbage) is a term for the mass of defunct, artificially created objects in space, most notably in Earth orbit, such as old satellites and spent rocket stages.
A space elevator is a proposed type of planet-to-space transportation system.
Space exploration is the discovery and exploration of celestial structures in outer space by means of evolving and growing space technology.
Space law encompasses national and international law governing activities in outer space.
Space manufacturing is the production of manufactured goods in an environment outside a planetary atmosphere.
The Space Race refers to the 20th-century competition between two Cold War rivals, the Soviet Union (USSR) and the United States (US), for dominance in spaceflight capability.
A space station, also known as an orbital station or an orbital space station, is a spacecraft capable of supporting crewmembers, which is designed to remain in space (most commonly as an artificial satellite in low Earth orbit) for an extended period of time and for other spacecraft to dock.
Space weather is a branch of space physics and aeronomy concerned with the time varying conditions within the Solar System, including the solar wind, emphasizing the space surrounding the Earth, including conditions in the magnetosphere, ionosphere, thermosphere, and exosphere.
A spacecraft is a vehicle or machine designed to fly in outer space.
Spaceflight (also written space flight) is ballistic flight into or through outer space.
Spaceflight osteopenia refers to the characteristic bone loss that occurs during spaceflight.
In physics, special relativity (SR, also known as the special theory of relativity or STR) is the generally accepted and experimentally well-confirmed physical theory regarding the relationship between space and time.
The speed of light in vacuum, commonly denoted, is a universal physical constant important in many areas of physics.
Sputnik 1 (or; "Satellite-1", or "PS-1", Простейший Спутник-1 or Prosteyshiy Sputnik-1, "Elementary Satellite 1") was the first artificial Earth satellite.
Standard conditions for temperature and pressure are standard sets of conditions for experimental measurements to be established to allow comparisons to be made between different sets of data.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction.
Stellar nucleosynthesis is the theory explaining the creation (nucleosynthesis) of chemical elements by nuclear fusion reactions between atoms within the stars.
Stellar parallax is the apparent shift of position of any nearby star (or other object) against the background of distant objects.
A stellar wind is a flow of gas ejected from the upper atmosphere of a star.
Stellar-wind bubble is a cavity light years across filled with hot gas blown into the interstellar medium by the high-velocity (several thousand km/s) stellar wind from a single massive star of type O or B. Weaker stellar winds also blow bubble structures, which are also called astrospheres.
A sub-orbital spaceflight is a spaceflight in which the spacecraft reaches space, but its trajectory intersects the atmosphere or surface of the gravitating body from which it was launched, so that it will not complete one orbital revolution.
In the physical sciences, subatomic particles are particles much smaller than atoms.
The Sun is the star at the center of the Solar System.
A supernova (plural: supernovae or supernovas, abbreviations: SN and SNe) is a transient astronomical event that occurs during the last stellar evolutionary stages of a star's life, either a massive star or a white dwarf, whose destruction is marked by one final, titanic explosion.
Taurus (Latin for "the Bull") is one of the constellations of the zodiac, which means it is crossed by the plane of the ecliptic.
Temperature is a physical quantity expressing hot and cold.
Theodore von Kármán ((szőllőskislaki) Kármán Tódor; 11 May 1881 – 6 May 1963) was a Hungarian-American mathematician, aerospace engineer, and physicist who was active primarily in the fields of aeronautics and astronautics.
Thermodynamic equilibrium is an axiomatic concept of thermodynamics.
The thermosphere is the layer of the Earth's atmosphere directly above the mesosphere and below the exosphere.
Thomas Digges (c. 1546 – 24 August 1595) was an English mathematician and astronomer.
Three-dimensional space (also: 3-space or, rarely, tri-dimensional space) is a geometric setting in which three values (called parameters) are required to determine the position of an element (i.e., point).
Timeline of knowledge about the interstellar medium and intergalactic medium.
This is a timeline of Solar System exploration ordered by date of spacecraft launch.
This is a timeline of known spaceflights, both manned and unmanned, sorted chronologically by launch date.
The trihydrogen cation, also known as protonated molecular hydrogen or, is one of the most abundant ions in the universe.
Uganda, officially the Republic of Uganda (Jamhuri ya Uganda), is a landlocked country in East Africa.
In astroparticle physics, an ultra-high-energy cosmic ray (UHECR) is a cosmic ray particle with a kinetic energy greater than eV, far beyond both the rest mass and energies typical of other cosmic ray particles.
The unified atomic mass unit or dalton (symbol: u, or Da) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass).
The United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) was established in 1959 (shortly after the launch of Sputnik) as an ad hoc committee.
The United Nations General Assembly (UNGA or GA; Assemblée Générale AG) is one of the six principal organs of the United Nations (UN), the only one in which all member nations have equal representation, and the main deliberative, policy-making and representative organ of the UN.
A United Nations resolution (UN resolution) is a formal text adopted by a United Nations (UN) body.
The Universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy.
Unmanned spacecraft are spacecraft without people ("man") on board, used for unmanned spaceflight.
The V-2 (Vergeltungswaffe 2, "Retribution Weapon 2"), technical name Aggregat 4 (A4), was the world's first long-range guided ballistic missile.
Vacuum is space devoid of matter.
Vacuum energy is an underlying background energy that exists in space throughout the entire Universe.
A Van Allen radiation belt is a zone of energetic charged particles, most of which originate from the solar wind, that are captured by and held around a planet by that planet's magnetic field.
The vapour pressure of water is the pressure at which water vapour is in thermodynamic equilibrium with its condensed state.
Venera 1 (Венера-1 meaning Venus 1), also known as Venera-1VA No.2 and occasionally in the West as Sputnik 8 was the first spacecraft to fly past Venus, as part of the Soviet Union's Venera programme.
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days.
Vertigo is a symptom where a person feels as if they or the objects around them are moving when they are not.
Cosmic voids are vast spaces between filaments (the largest-scale structures in the universe), which contain very few or no galaxies.
Vomiting, also known as emesis, puking, barfing, throwing up, among other terms, is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose.
Vostok 1 (Восто́к, East or Orient 1) was the first spaceflight of the Vostok programme and the first manned spaceflight in history.
Voyager 1 is a space probe launched by NASA on September 5, 1977.
The Voyager program is an American scientific program that employs two robotic probes, Voyager 1 and Voyager 2, to study the outer Solar System.
The warm–hot intergalactic medium (WHIM) refers to a sparse, warm-to-hot (105 to 107 K) plasma that cosmologists believe to exist in the spaces between galaxies and to contain 40–50% of the baryons (that is, 'normal matter' which exists as plasma or as atoms and molecules, in contrast to dark matter) in the universe at the current epoch.
The weather satellite is a type of satellite that is primarily used to monitor the weather and climate of the Earth.
Western culture, sometimes equated with Western civilization, Occidental culture, the Western world, Western society, European civilization,is a term used very broadly to refer to a heritage of social norms, ethical values, traditional customs, belief systems, political systems and specific artifacts and technologies that have some origin or association with Europe.
Westphalian sovereignty, or state sovereignty, is the principle of international law that each nation-state has exclusive sovereignty over its territory.
White blood cells (WBCs), also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders.
The Wilkinson Microwave Anisotropy Probe (WMAP), originally known as the Microwave Anisotropy Probe (MAP), was a spacecraft operating from 2001 to 2010 which measured temperature differences across the sky in the cosmic microwave background (CMB) – the radiant heat remaining from the Big Bang.
William Alison "Bill" Anders (born October 17, 1933), (Maj Gen, USAFR, Ret.), is a former United States Air Force officer, electrical engineer, nuclear engineer, NASA astronaut, and businessman.
William Gilbert (24 May 1544 – 30 November 1603), also known as Gilberd, was an English physician, physicist and natural philosopher.
Yuri Alekseyevich Gagarin (p; 9 March 1934 – 27 March 1968) was a Soviet pilot and cosmonaut.
Zhang Heng (AD 78–139), formerly romanized as Chang Heng, was a Han Chinese polymath from Nanyang who lived during the Han dynasty.
Zodiacal light (also called false dawn when seen before sunrise) is a faint, diffuse, and roughly triangular white glow that is visible in the night sky and appears to extend from the Sun's direction and along the zodiac, straddling the ecliptic.
61 Cygni Not to be confused with 16 Cygni, a more distant system containing two G-type stars harboring the gas giant planet 16 Cygni Bb.
Boundary to space, Cis-lunar space, Cislunar, Cislunar medium, Cislunar space, Deepspace, Geospace, Inter-planetary space, Intergalactic gas, Intergalactic medium, Intergalactic space, Interplanetary space, Interstellar space, Outer Space, Outer-space, Space border, Space/universe.