A

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David

Darling

Encyclopedia of Science: A entries

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

A For Andromeda
"A" series of German rockets
A star
a'a
abacus
abalone
Abbott, Edwin Abbott (1838–1926)
Abbott, Ira H. (1906–1988)
ABC conjecture
abdomen
abducens nerve
abduction
Abel, John Jacob (1857–1938)
Abel, Niels Henrik (1802–1829)
Abelian group
Abell 39
Abell cluster
Aberdeen Proving Ground
aberration, optical
aberration of starlight
abiogenesis
abiotic
ablation
Able
abracadabra
abrasive
abscess
abscisic acid
abscission
absolute
absolute magnitude
absolute value
absolute zero
absorbed dose
absorber
absorptance
absorption
absorption band
absorption line
absorption nebula
absorption spectrum
abstract algebra
Abu'l Wafa (AD 940–998)
abundant number
Abyss, The
abyssal zone
acanthion
Acathocephala (spiny-headed worms)
acapulcoite
Acarina
Acasta Formation
acceleration
acceleration due to gravity
acceleration stress
acceleration tolerance
accelerator
accelerometer
ACCESS (Advanced Cosmic-ray Composition Experiment on the Space Station)
accessory nerve
accessory organ
acclimatization
accommodation
accretion
accretion disk
accretionary lapilli
accretionary wedge
accuracy
ACE (Advanced Composition Explorer)
ACE inhibitor
acebutolol
acetabulum
acetaldehyde
acetate
acetic acid
acetogens
acetone
acetyl coenzyme A
acetylcholine
acetylcysteine
acetylene
achene
Achernar (Alpha Eridani)
Acheson, Edward Goodrich (1856–1931)
Achilles (asteroid)
Achilles tendon
achondrite
achondroplasia
achromatic
acid
acid anhydride
acid chloride
acid rain
acid salt
acidophiles
acidosis
Ackermann function
acne
acoustic shielding
acoustics
ACOUSTICS AND MUSIC
acquired immune deficiency syndrome (AIDS)
acquisition
acridine
ACRIMSAT
acromegaly
acromion
Acrux (Alpha Crucis)
ACRV (Assured Crew Return Vehicle)
actin
actinide
actinium
Actinopterygii (ray-finned fish)
action
action at a distance
action potential
activation cross section
activation energy
active beam
active fault
active galactic nucleus
active galaxy
active optics
active region
active site
active transport
activity
ACTS (Advanced Communications Technology Satellite)
acupuncture
acute
acute respiratory distress syndrome
acyl group
Ad Astra Rocket Company
Adams, John (1735–1826)
Adams, John Couch (1819–1892)
Adams, Walter Sidney (1876–1956)
Adam's apple
Adamski, George (1891–1965)
adaptation
adaptive optics
adaptive radiation
adder
addiction
Addison, Joseph (1672–1719)
Addison's disease
addition
addition reaction
adduction
adductor magnus
ADE (Air Density Explorer)
adenine
adenoids
adenosine triphosphate (ATP)
adenovirus
adenovirus infection
ADEOS (Advanced Earth Observing Satellite)
Adhara (Epsilon Canis Majoris)
ADHD (Attention Deficit–Hyperactive Disorder)
adhesion
adhesive
adiabatic process
adipose tissue
admittance
Adonis (asteroid)
Adrastea
adrenal gland
adrenaline
adrenocorticotropic hormone (ACTH)
adsorption
advance of perihelion
Advanced Fiber-Optic Echelle spectrometer
ADVANCED PROPULSION CONCEPTS
adventitious
AE Aurigae
Ae star
AEM (Applications Explorer Mission)
aeolian structure
aeolipile
aeration
aerial
Aerial Phenomena Research Organization (APRO)
Aerial Target (A.T.)
Aerobee
aerobic
aerobraking
aerocapture
aerodynamics
AERODYNAMICS AND AERONAUTICS
aeroembolism
aerogel
Aerojet Corporation
aeronautics
aeronomy
Aeros
aerosol
aerospace
AEROSPACE ADMINISTRATORS
AEROSPACE AND RELATED COMPANIES
aerospace medicine
aestivation
affine geometry
AFSATCOM (Air Force Satellite Communications System)
afterburner
afterglow
aftershock
agar
Agassiz, Alexander (1835–1910)
agate
Agena
agglomerate
agglutinates
agglutinin
aging
Agnatha (jawless fish)
Agnesi, Maria Gaetana (1718–1799)
agranulocytosis
Agrest, Matest M. (1915–2005)
Agrest, Mikhail
Ahnighito meteorite
Ahrens, Wilhelm Ernst Martin Georg (1872–1927)
AI Velorum star
Aiken, Howard (1900–1973)
aileron
AIM (Aeronomy of Ice in the Mesosphere)
air
air brake
air conditioner
Air Force Flight Test Center
Air Force Space Command
Air Materiel Command
air sac
air speed indicator
air start
Air Technical Intelligence Center
air-breathing engine
airfoil
airglow
airlock
airmass
airplane
airship
airspace
airways
Airy, George Biddell (1801–1892)
Airy disk
Aitken, Robert Grant (1864–1951)
Akebono
Akiyama, Toyohiro (1944–)
Al Niyat (Sigma and Tau Scorpii)
alabaster
Alais meteorite
alanine
Albategnius (al-Battani, Muhammad ibn Jabir) (c. 850–929)
albedo
Albertus Magnus (1193–1280)
albino
Albireo (Beta Cygni)
albite
albumin
Alcantara Launch Center
alchemy
alcohols
Alcubierre, Miguel (1964–)
Alcubierre warp drive
Alcuin (735–804)
Alcyone (Eta Tauri)
Aldebaran (Alpha Tauri)
aldehyde
Alder, Kurt (1902–1958)
Alderamin (Alpha Cephei)
aldosterone
Aldrin, Edwin Eugene ("Buzz"), Jr. (1930–)
Alembert, Jean le Rond d' (1717–1783)
alembic
Alencon Spaceman
aleph
Alexander's Horned Sphere
Alexandra family (of asteroids)
Alexandrian school
ALEXIS (Array of Low Energy X-ray Imaging Sensors)
Alfirk (Beta Cephei)
Alfvén, Hannes Olof Gösta (1908–1995)
algae
ALGEBRA
algebra
algebraic function
algebraic geometry
algebraic number
algebraic operation
algebraic topology
Algieba (Gamma Leonis)
Algol (Beta Persei)
Algonquin Radio Observatory
algorithm
algorithmic complexity
ALH 84001
Alhambra
Alhazen (Abu Ali al Hassan ibn al Haitham) (c .965–c. 1040)
Alhena (Gamma Geminorum)
alicyclic compound
alien
Alien
alien abduction
alien life, a gallery of possibilities
alimentary canal
Alinda group (of asteroids)
Alioth (Epsilon Ursae Majoris)
aliphatic compound
aliquot part
alizarin
Alkaid (Eta Ursae Majoris)
alkali
alkali flats
alkali metal
alkaline battery
alkaline earth metal
alkaliphile
alkaloid
alkalosis
alkanes
alkenes
Al-Khowarizmi (c. 780–850)
alkyd
alkyl group
alkyl halide
alkylation
alkynes
Allais paradox
Allan Hills
allantois
Allegheny Observatory
allele
Allen, Irwin (1916–1991)
Allen Telescope Array (ATA)
Allende meteorite
allergy
allogenic
allopatric speciation
allotropy
alloy
all-sky camera
all-sky survey
alluvial fan
alluvium
ALMA
Almaak (Gamma Andromedae)
Almagest
almanac
Almaz
almond tree
almost perfect number
Alnair (Alpha Gruis)
Alnath (Beta Tauri)
Alnilam (Epsilon Orionis)
Alnitak (Zeta Orionis)
alopecia
ALOS (Advanced Land Observing Satellite)
Alouette
Alpha Centauri
Alpha Cygni star
alpha particle
alpha-1 antitrypsin deficiency
Alpha2 Canum Venaticorum star
alphametic
Alphard (Alpha Hydrae)
Alphekka (Alpha Coronae Borealis)
Alpher, Ralph Asher (1921–2007)
Alpheratz (Alpha Andromedae)
Alphonsine Tables
Alphonsus
Al-Sufi, Abd al-Rahman (AD 903–986)
Altair (Alpha Aquilae)
altazimuth mounting
Altekruse puzzle
alternation of generations
alternate
alternating current
ALTERNATIVE FORMS OF LIFE
altimeter
altitude
altitude sickness
Aludra (Eta Canis Majoris)
alum
aluminum
aluminizing
Alvarez, Luis Walter (1911–1988)
alveolus
AM Canum Venaticorum star
AM Herculis star
amalgam
Amalthea
Amazonian epoch
Ambartsumian, Viktor Amazaspovich (1908–1996)
Ambartsumian's Knot
amber
ambiguous figure
ambipolar diffusion
AMC
American Astronautical Society (AAS)
American Institute of Aeronautics and Astronautics (AIAA)
American Rocket Society
americium
Ames, Milton B. (1913–1992)
Ames Research Center
Ames room
amethyst
amicable numbers
amide
amine
amino acids
amino acids in space
amino group
ammeter
ammonia
ammonia-based life
ammonite
amnesia
amniocentesis
amnion
amniotic fluid
amniotic sac
amoeba
amoeboid
Amor group
amorphous
amorphous semiconductor
amount of substance
Ampère, André Marie (1775–1836)
ampere
amphibian
amphibole
amphipod
amphoteric
amplifier
amplitude
amplitude modulation
AMPTE (Active Magnetosphere Particle Tracer Explorer)
AMS (Alpha Magnetic Spectrometer)
amygdala
amyl compound
amylase
amyloid
amyloidosis
amyotrophic lateral sclerosis
anabolism
anacoustic zone
anaerobe
anagram
analemma
analgesic
anallagmatic curve
analogous
analysis
ANALYTICAL CHEMISTRY
analytical geometry
ANALYTICAL GEOMETRY
anamorphosis
Ananke
anaphase
anaphylaxis
anaplasmosis
anastigmat(ic)
anastomosis
anatomical position
anatomical snuffbox
anatomy
ANATOMY AND PHYSIOLOGY
Anaxagoras of Clazomenae (c. 500–c. 428 BC)
Anaximander of Miletus (c. 610–c. 540 BC)
Anaximenes of Miletus (c. 585–525 BC)
ancient astronaut hypothesis
ancient philosophy, related to the possibility of extraterrestrial life
ancient science
andalusite
Anders, William Alison (1933–)
Anderson, Carl David (1905–1991)
andesite
Andoya Rocket Range
Andrews Air Force Base
androecium
androgen
android
Andromeda (constellation)
Andromeda Galaxy (M31, NGC 224)
Andromedids
andromonoecious
anechoic chamber
anemia
anemic spiral galaxy
anemometer
anemophily
anencephaly
anesthesia
aneurysm
Angara
Angelina
angina
angiography
angioplasty
angiosperm
angiotensin
angle
angle of attack
angle of incidence
angle of refraction
anglesite
Anglo-Australian Observatory
Anglo-Australian Telescope
angrite
angstrom (unit)
Ångström, Anders Jonas (1814–1874)
angular acceleration
angular diameter
angular momentum
angular units
angular velocity
anhydride
anhydrite
anhydrobiosis
Anik
aniline
animal
animal behavior
animal cell
animals in space
animals' mathematical ability
anisotropy
ankle
ankylosis
Annelida (true worms)
annihilation
annual (plant)
annual ring
annual variation
annulus
anode
anodizing
anomalous X-ray pulsar
anomaly
anorthite
anorthosite
ANS (Astronomische Nederlandse Satelliet)
ansa
Ansari X-prize
Ansbro, Eamonn
ant
Ant Nebula (Menzel 3)
antagonist
Antarctic Dry Valleys
Antarctic Search for Meteorites
Antares (Alpha Scorpii)
antenna (physics)
antenna (zoology)
antenna directivity
antenna temperature
Antennae (NGC 4038 and NGC 4039)
anterior
anterior facial vein
anther
antheridium
anthocyanin
Anthony, Piers (1934–)
anthracene
anthracite
anthrax
anthropic principle
anthropoid
anthropoid apes
anthropology
anthropomorphism
antibiotic
antibody
anticline
anticoagulant
anticyclone
antidepressant
antidiuretic hormone (ADH)
anti-g suit
antigen
antigravity
antigravity houses and hills
antihistamine
Antikythera Mechanism
antimatter
antimatter propulsion
antimatter-driven sail
antimony
antinode
Antiope (asteroid)
antioxidant
antiparticles
antiphospholipid antibody syndrome
antiprism
antisense
antiseptic
antitail
antitoxin
antlerite
Antlia
Antlia Dwarf Galaxy
Antoniadi, Eugene Michael (1870–1944)
Antoniadi scale
Anura
anus
AO Cassiopeiae
aorta
aortic dissection
aortic valve
aortography
Ap star
Apache Point Observatory
apatite
ape
apergy
aperiodic tiling
aperture
aperture synthesis
Apéry's constant
apex (astronomy)
apex (geometry)
aphasia
aphelion
aphid
apical meristem
aplastic anemia
apoapsis
apochromatic
apocrine gland
Apoda
apogee
apohele
Apollo (asteroid)
Apollo 7
Apollo 8
Apollo 9
Apollo 10
Apollo 11
Apollo 12
Apollo 13
Apollo 14
Apollo 15
Apollo 16
Apollo 17
Apollo group
Apollo Project
Apollonius of Perga (c. 262–c. 190 BC)
Apollonius problem
Apollo-Soyuz Test Project
aponeurosis
Apophis
apoptosis
apostilb (unit)
apothecaries' weights
apothem
apparent horizon
apparent magnitude
apparition
appendicitis
appendix
Appleton, Edward Victor (1892–1965)
approximation
APPROXIMATIONS AND AVERAGES
apsis
Apus (constellation)
Aqua
aqua regia
aqualung
Aquarids
Aquarius (constellation)
Aquarius (spacecraft)
Aquarius Dwarf
aqueous humor
aqueous solution
aquifer
Aquila
Aquinas, Thomas (1225–1274)
Ara (constellation)
Arabian astronomy
Arabic numerals
arachnid
arachnoid membrane
Arago, Dominique Francois Jean (1786–1853)
Arago point
aragonite
arbelos
arc
arc lamp
Arcetri Astrophysical Observatory
arch
archaea
archaeobacteria
Archaeopteryx
archegonium
archenteron
archeoastronomy
Arches Cluster
Archimedean screw
Archimedean solid
Archimedean spiral
Archimedean tessellation
Archimedes (c. 287–212 BC)
Archimedes and the burning mirrors
Archimedes' cattle problem
Archimedes' principle
archipelago
Archytas (c. 428–c. 350 BC)
arcjet
arcsecond
Arcturus (Alpha Bootis)
area
Area 51
area rule
Arecibo message
Arecibo Observatory
Arecibo radio telescope
Arend-Roland, Comet
areolar tissue
Ares (launch vehicles)
Ares Vallis
arète
Argand burner
Argand diagram
Argelander, Friedrich Wilhelm August (1799–1875)
arginine
Argo Navis
argon
ARGOS (Advanced Research and Global Observation Satellite)
argument
argument of perihelion
Argus, Project
Ariane
Arianespace
Ariel (moon of Saturn)
Ariel (UK satellites)
Aries (constellation)
Aries sounding rocket
Ariosto, Ludovico (1474–1533)
Aristarchus (crater)
Aristarchus of Samos (c. 320–c. 250 BC)
Aristotle of Stagira (384–322 BC)
Aristotle's wheel
arithmetic
ARITHMETIC
arithmetic mean
arithmetic sequence
ark, interstellar
Arkhipov, Alexey V. (1959–)
arkose
Arkwright, Richard (1732–1792)
armature
armillary sphere
Armstrong, Neil Alden (1930–2012)
Army Ballistic Missile Agency (ABMA)
Arnold, Henry H. (Hap) (1886–1950)
Arnold, Kenneth (1915–1984)
aromatic compound
aromatic herbs
Arouet, Francois-Marie (1694–1778)
Around the Moon
Arp, Halton Christian (1927–2013)
array
Arrest, Heinrich Ludwig d' (1822–1875)
Arrhenius, Svante August (1859–1927)
arrow of time
Arrow paradox
arrhythmias
arsenic
arsenic-based life
arsenopyrite
ARTEMIS (Advanced Relay Technology Mission)
arterial blood gas analysis
arteriography
arteriole
arteriosclerosis
artery
arthritis
arthropod
arthroscope
articular capsule
artifacts, alien
artificial gravity
artificial insemination
artificial intelligence
artificial life
artificial satellite
artificial selection
Artiodactyla
ARTV (Advanced Reentry Test Vehicle)
Aryabhata the Elder (AD 476–c. 550)
Aryabhata (satellite)
aryl group
arytenoid cartilages
Arzachel (Al-Zarqali, Abu Ishaq Ibrahim ibn Yahya) (1028–1087)
asbestos
Asperger syndrome
Asbolus
ASCA
ascariasis
ascending node
ascending pharyngeal artery
Asclepius (asteroid)
Ascomycetes
asexual reproduction
ash
ashen light
ASI (Agenzia Spaziale Italiano)
Asiago Astrophysical Observatory
Asian and medieval science
Asimov, Isaac (1920–1992)
ASLV (Advanced Satellite Launch Vehicle)
asparagine
aspartame
aspect
aspect ratio
asphalt
asphyxia
aspirin
assay
assaying
ASSET (Aerothermodynamic Elastic Structural Systems Environmental Tests)
associationism
associations, stellar
associative
astatine
asterism
Asterix
asteroid
asteroid belt
asteroid mining
asteroid spectral types
ASTEROIDS, CENTAURS, AND KUIPER BELT OBJECTS: INDIVIDUAL
ASTEROIDS AND OTHER MINOR PLANETS: TYPES AND GROUPS
asthenosphere
asthma
astigmatism
Aston, Francis William (1877–1945)
Astraglossa
astringent
Astro (shuttle science payload)
Astro- (Japanese satellites)
Astro-E
Astro-F
ASTROBIOLOGY
astrobiology
Astrobiology Institute
astrobleme
astrochemistry
astrocyte
astroengineering
astroid
astrolabe
astrometry
Astron
ASTRONAUTS AND COSMONAUTS
Astronomer Royal
ASTRONOMERS AND ASTROPHYSICISTS
ASTRONOMICAL CATALOGUES
ASTRONOMICAL QUANTITIES
astronomical unit
astronomy
astrophotography
astrophysics
astroseismology
astrosociology
Asuka
asymmetric carbon atom
asymmetric drift
asymptote
asymptotic giant branch
Atacama Large Millimeter Array
atavism
ataxia
ataxite
Atchley, Jr., Dana W.
Aten group
Athena
Athena (launch vehicle)
atherosclerosis
athlete's foot
ATIC
Atiyah, Michael Francis (1929–)
Atlantis (Shuttle orbiter)
Atlantis, legend of
Atlas (launch vehicle)
Atlas (moon)
ATLAS particle detector
atmosphere
atmosphere (unit of pressure)
atmospheric braking
atmospheric circulation
atmospheric extinction
atmospheric halo
ATMOSPHERIC PHENOMENA AND STRUCTURES
atmospheric pressure
atmospheric refraction
atmospheric window
ATNF
atoll
atom
atomic and molecular mass
ATOMIC AND NUCLEAR PHYSICS
atomic clock
atomic force microscope
atomic number
atomic orbital
atomic theory of matter
atomic volume
atomicity
atomism
Atoms For Peace Galaxy (NGC 7252)
Atomium, The
atopic dermatitis
ATP
Atria (Alpha Trianguli Australis)
atrial natriuretic peptide
atrial fibrillation
atrial septal defect (hole-in-the-heart)
atrium
atropine
ATS (Applications Technology Satellite)
attitude
attractor
A-type asteroid
AU
Aubel's theorem
aubrite
auditory canal
auditory nerve
auditory ossicles
Auger, Pierre Victor (1899–1993)
Auger effect
augite
Augustine, Norman R. (1935–)
Aura
auricle
Auriga
aurora
auscultation
Australian Space Research Institute
Australia Telescope National Facility
australopithecine
autism
autocatalysis
autoclave
autogyro
autoimmune disease
autoimmune lymphoproliferative syndrome (ALPS)
automated external defibrillator
Automated Transfer Vehicle
automobile
automorphic number
automorphism
autonomic nervous system
autopilot
autopoeisis
autosomal dominant
autosomal recessive
autosome
autotrophs
auxin
avalanche
Averroës (1126–1198)
Avogadro, Amedeo (1776–1856)
Avdeyev, Sergei (1956–)
average
averted vision
AVIATION PIONEERS
avionics
Avior (Epsilon Carinae)
Avogadro constant
avoirdupois
Avrocar
Axelrod, Julius (1912–2004)
axil
axilla
axillary artery
axillary vein
axiom of choice
axion
axis
axis of symmetry
axolotl
axon
azathioprine
azeotropic mixture
azimuth
azimuthal quantum number
azo compound
Azur
azurite