Wikipedia:Vital articles/Level/4/Physical sciences

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=Physical sciences =

Total 1,101 articles.

Basics

 * 1)  Science (Level 1)
 * 2)  Scientific method (Level 3)
 * 3)   Nature (Level 3)
 * 4)  Experiment
 * 5)  Field research
 * 6)  Laboratory
 * 7)  Observation
 * 8)  Scientific law
 * 9)  Research
 * 10)  Scientific modelling
 * 11)  Scientific theory

Measurement

 * This section contains units of measurement and articles on metrology. For the measured quantities, see Science and Mathematics sections. For timekeeping and navigation, see Everyday Life and Technology. For measurement errors, see Statistics section in Mathematics.

Measurement: General

 * 1)  Measurement (Level 3)
 * 2)  Accuracy and precision
 * 3)  Metrology
 * 4)  Unit of measurement
 * 5)  Natural units
 * 6)  Planck units

Measurement systems

 * 1)  Metric system
 * 2)   International System of Units (Level 3)
 * 3)  United States customary units
 * 4)  Imperial units

Time

 * 1)  Second
 * 2)  Minute
 * 3)  Hour
 * 4)  Day (Level 3)
 * 5)  Week
 * 6)  Month
 * 7)  Year (Level 3)

Length and distance

 * 1)  Inch
 * 2)  Foot
 * 3)  Cubit
 * 4)  Metre
 * 5)  Mile
 * 6)  Nautical mile
 * 7)  Astronomical unit
 * 8)  Light-year
 * 9)  Parsec

Area

 * 1)  Acre
 * 2)  Hectare

Volume

 * 1)  Gallon
 * 2)  Litre

Energy, force and pressure

 * 1)  Atmosphere
 * 2)  Calorie
 * 3)  Electronvolt
 * 4)  Joule
 * 5)  Newton
 * 6)  Pascal

Mass

 * 1)  Dalton (unit)
 * 2)  Kilogram
 * 3)  Ton
 * 4)  Pound
 * 5)  Ounce

Velocity

 * 1)  Knot

Angle

 * 1)  Degree
 * 2)  Radian
 * 3)  Steradian

Light

 * 1)  Candela
 * 2)  Lumen
 * 3)  Lux

Temperature

 * 1)  Celsius
 * 2)  Fahrenheit
 * 3)  Kelvin

Electromagnetism

 * 1)  Ampere
 * 2)  Farad
 * 3)  Coulomb
 * 4)  Henry
 * 5)  Hertz
 * 6)  Ohm
 * 7)  Siemens
 * 8)  Tesla
 * 9)  Volt
 * 10)  Watt
 * 11)  Weber

Amount of substance

 * 1)  Mole

Data

 * 1)  Byte
 * 2)  Bit

Radioactivity

 * 1)  Becquerel
 * 2)  Gray
 * 3)  Sievert

Other

 * 1)  Decibel

Astronomy

 * For astronomical instruments, see Technology: Optical Technology.

Basics

 * 1)  Astronomy (Level 2)
 * 2)  Astronomical object
 * 3)  Astrophysics
 * 4)   Extraterrestrial life

Observational astronomy

 * 1)  Observatory
 * 2)  Luminosity
 * 3)  Magnitude
 * 4)  Extinction

Solar System

 * 1)  Solar System (Level 2)
 * 2)  Sun (Level 2)
 * 3)  Mercury (Level 3)
 * 4)  Venus (Level 3)
 * 5)  Earth (Level 1)
 * 6)  Moon (Level 2)
 * 7)  Mars (Level 3)
 * 8)  Asteroid belt
 * 9)  Ceres
 * 10)   Jupiter (Level 3)
 * 11)  Io
 * 12)  Europa
 * 13)  Ganymede
 * 14)  Callisto
 * 15)  Saturn (Level 3)
 * 16)  Enceladus
 * 17)  Titan
 * 18)  Uranus (Level 3)
 * 19)  Neptune (Level 3)
 * 20)  Triton
 * 21)  Kuiper belt
 * 22)  Pluto
 * 23)  Eris
 * 24)  Oort cloud
 * 25)  Interplanetary medium

Notable stars

 * 1)  Alpha Centauri
 * 2)  Arcturus
 * 3)  Betelgeuse
 * 4)  Canopus
 * 5)  Capella
 * 6)  Polaris
 * 7)  Procyon
 * 8)  Rigel
 * 9)  Sirius
 * 10)  Vega

Notable galaxies

 * 1)  Local Group
 * 2)  Milky Way (Level 3)
 * 3)  Galactic Center
 * 4)  Sagittarius A*
 * 5)  Andromeda Galaxy
 * 6)  Large Magellanic Cloud
 * 7)  Small Magellanic Cloud
 * 8)  Triangulum Galaxy
 * 9)  Centaurus A
 * 10)  Messier 87
 * 11)  Pinwheel Galaxy
 * 12)  Whirlpool Galaxy

Notable nebulae

 * 1)  Carina Nebula
 * 2)   Crab Nebula
 * 3)  Eagle Nebula
 * 4)  Horsehead Nebula
 * 5)  Orion Nebula
 * 6)  Ring Nebula

Other notable objects

 * 1)  3C 273
 * 2)  Cygnus X-1
 * 3)  Halley's Comet
 * 4)  Hyades
 * 5)  Omega Centauri
 * 6)   Pleiades
 * 7)  Virgo Supercluster
 * 8)  Virgo Cluster

Celestial mechanics

 * 1)  Celestial mechanics
 * 2)  Orbit (Level 3)
 * 3)  Barycenter (astronomy)
 * 4)  Tidal locking
 * 5)  Eclipse
 * 6)  Lunar eclipse
 * 7)  Solar eclipse
 * 8)  Kepler's laws of planetary motion
 * 9)  Lagrange point
 * 10)  Night

Orbital mechanics

 * 1)  Orbital mechanics
 * 2)  Escape velocity
 * 3)  Geostationary orbit
 * 4)  Geosynchronous orbit
 * 5)  Gravitational acceleration
 * 6)  Gravity assist
 * 7)  Low Earth orbit

Celestial sphere

 * 1)  Celestial sphere
 * 2)  Astronomical coordinate systems
 * 3)  Equatorial coordinate system
 * 4)  Equinox
 * 5)  Ecliptic
 * 6)  Horizon
 * 7)  Solstice
 * 8)  Zodiac

Constellations

 * 1)  Constellation
 * 2)  Canis Major
 * 3)  Cassiopeia
 * 4)  Centaurus
 * 5)  Crux
 * 6)  Orion
 * 7)  Ursa Major
 * 8)  Ursa Minor

Astrometry

 * 1)  Astrometry
 * 2)  Albedo
 * 3)  Cosmic distance ladder
 * 4)  Parallax
 * 5)  Photometry

Basics

 * 1)  Outer space (Level 3)
 * 2)  Galaxy (Level 3)
 * 3)   Black hole (Level 3)
 * 4)  Event horizon
 * 5)  Supermassive black hole
 * 6)  Galaxy groups and clusters
 * 7)  Supercluster
 * 8)  Interstellar medium
 * 9)  Nebula
 * 10)  Dark nebula
 * 11)  Molecular cloud
 * 12)  Great Attractor
 * 13)  H II region
 * 14)  Void (astronomy)
 * 15)  Cosmic ray

Galaxy morphological classification

 * 1)  Galaxy morphological classification
 * 2)  Spiral galaxy
 * 3)  Barred spiral galaxy
 * 4)  Elliptical galaxy
 * 5)  Lenticular galaxy
 * 6)  Irregular galaxy
 * 7)  Dwarf galaxy

Active galactic nucleus

 * 1)  Active galactic nucleus
 * 2)  Blazar
 * 3)  Quasar
 * 4)  Radio galaxy
 * 5)  Seyfert galaxy

Physical cosmology

 * 1)  Physical cosmology (Level 3)
 * 2)  Universe (Level 2)
 * 3)  Observable universe
 * 4)  Chronology of the universe
 * 5)  Ultimate fate of the universe
 * 6)   Big Bang (Level 3)
 * 7)   Inflation (cosmology)
 * 8)   Cosmic microwave background
 * 9)  Galaxy formation and evolution
 * 10)  Formation and evolution of the Solar System
 * 11)  Nebular hypothesis
 * 12)   Dark matter
 * 13)  Dark energy
 * 14)  Cosmological constant
 * 15)  Redshift
 * 16)   Hubble's law

Planetary science

 * 1)  Planet (Level 3)
 * 2)  Terrestrial planet
 * 3)  Giant planet
 * 4)   Exoplanet
 * 5)  Natural satellite (Level 3)
 * 6)   Comet (Level 3)
 * 7)  Minor planet
 * 8)   Asteroid (Level 3)
 * 9)  Dwarf planet
 * 10)  Meteoroid
 * 11)  Atmosphere
 * 12)  Meteor shower
 * 13)  Impact event
 * 14)  Ring system

Stellar astronomy

 * 1)  Star (Level 3)
 * 2)  Variable star
 * 3)  Supernova (Level 3)
 * 4)  Gamma-ray burst
 * 5)  Nova
 * 6)  Pulsar
 * 7)  Cepheid variable
 * 8)  Star system
 * 9)  Planetary system
 * 10)   Binary star
 * 11)  Star cluster
 * 12)  Stellar classification
 * 13)  Stellar evolution
 * 14)  Star formation
 * 15)  Starburst galaxy
 * 16)   Planetary nebula
 * 17)  Protostar
 * 18)  Main sequence
 * 19)  Giant star
 * 20)  Red giant
 * 21)  Supergiant
 * 22)  Wolf–Rayet star
 * 23)  White dwarf
 * 24)  Neutron star
 * 25)  Stellar kinematics
 * 26)  Stellar magnetic field
 * 27)  Stellar structure
 * 28)  Solar wind
 * 29)  Metallicity
 * 30)  Brown dwarf
 * 31)  Hertzsprung–Russell diagram

Chemistry

 * For biochemistry and chemical biology, see: Biology and health sciences; for chemical industry, see: Technology.

Chemistry: General

 * 1)  Chemistry (Level 2)
 * 2)  Organic chemistry (Level 3)
 * 3)  Inorganic chemistry (Level 3)
 * 4)  Physical chemistry (Level 3)
 * 5)  Electrochemistry
 * 6)  Electrolysis
 * 7)  Environmental chemistry
 * 8)  Medicinal chemistry
 * 9)  Nuclear chemistry
 * 10)  Nuclide
 * 11)  Organometallic chemistry
 * 12)  Phase diagram
 * 13)  Photochemistry
 * 14)  Polymer chemistry
 * 15)  Polymer
 * 16)   Quantum chemistry
 * 17)  Materials science
 * 18)   Alchemy
 * 19)  Chemical substance
 * 20)  Amount of substance
 * 21)  Chemical synthesis
 * 22)  Conservation of mass
 * 23)  pH

Chemical reactions

 * 1)  Chemical reaction (Level 3)
 * 2)  Acid–base reaction (Level 3)
 * 3)  Catalysis (Level 3)
 * 4)  Chemical equation
 * 5)  Chemical equilibrium
 * 6)  Chemical formula
 * 7)  Chemical kinetics
 * 8)  Combustion
 * 9)  Corrosion
 * 10)  Redox (Level 3)
 * 11)  Haber process
 * 12)  Radical
 * 13)  Reaction mechanism
 * 14)  Substitution reaction

Chemical bonds

 * 1)  Chemical bond (Level 3)
 * 2)  Molecule (Level 3)
 * 3)  Ionic bonding
 * 4)  Covalent bond
 * 5)  Metallic bonding
 * 6)  Intermolecular force
 * 7)  Hydrogen bond
 * 8)  Valence bond theory

Separation processes

 * 1)  Chromatography
 * 2)  Distillation
 * 3)  Filtration

Analytical chemistry

 * 1)  Analytical chemistry
 * 2)  Spectroscopy
 * 3)  Absorption spectroscopy
 * 4)  Mass spectrometry

Basics

 * 1)  Chemical element (Level 2)
 * 2)  Periodic table (Level 3)
 * 3)  Allotropy
 * 4)  Atomic number
 * 5)  Atomic mass

Chemical element groups

 * 1)  Metal (Level 3)
 * 2)  Alkali metal
 * 3)  Alkaline earth metal
 * 4)  Lanthanide
 * 5)  Actinide
 * 6)  Transition metal
 * 7)  Metalloid
 * 8)  Halogen
 * 9)  Noble gas
 * 10)  Synthetic element

Chemical elements

 * 1)  Hydrogen (Level 3)
 * 2)  Helium


 * 1)  Lithium
 * 2)  Beryllium
 * 3)  Boron
 * 4)  Carbon (Level 3)
 * 5)  Diamond
 * 6)  Graphite
 * 7)  Carbon nanotube
 * 8)  Nitrogen (Level 3)
 * 9)  Oxygen (Level 3)
 * 10)   Ozone
 * 11)  Fluorine
 * 12)   Neon


 * 1)  Sodium
 * 2)  Magnesium
 * 3)  Aluminium (Level 3)
 * 4)  Silicon (Level 3)
 * 5)  Phosphorus (Level 3)
 * 6)  Sulfur (Level 3)
 * 7)  Chlorine
 * 8)   Argon


 * 1)  Potassium
 * 2)  Calcium
 * 3)  Scandium
 * 4)   Titanium
 * 5)  Vanadium
 * 6)  Chromium
 * 7)   Manganese
 * 8)  Iron (Level 3)
 * 9)  Cobalt
 * 10)  Nickel
 * 11)  Copper (Level 3)
 * 12)  Zinc
 * 13)  Gallium
 * 14)  Germanium
 * 15)  Arsenic
 * 16)  Selenium
 * 17)  Bromine
 * 18)  Krypton


 * 1)  Rubidium
 * 2)  Strontium
 * 3)  Yttrium
 * 4)  Zirconium
 * 5)  Niobium
 * 6)  Molybdenum
 * 7)  Technetium
 * 8)  Ruthenium
 * 9)  Rhodium
 * 10)   Palladium
 * 11)   Silver (Level 3)
 * 12)  Cadmium
 * 13)  Indium
 * 14)  Tin
 * 15)  Antimony
 * 16)  Tellurium
 * 17)  Iodine
 * 18)  Xenon


 * 1)  Caesium
 * 2)  Barium
 * 3)  Lanthanum
 * 4)   Cerium
 * 5)  Praseodymium
 * 6)  Neodymium
 * 7)  Promethium
 * 8)  Samarium
 * 9)  Europium
 * 10)  Gadolinium
 * 11)  Terbium
 * 12)  Dysprosium
 * 13)  Holmium
 * 14)  Erbium
 * 15)  Thulium
 * 16)  Ytterbium
 * 17)  Lutetium
 * 18)  Hafnium
 * 19)  Tantalum
 * 20)  Tungsten
 * 21)  Rhenium
 * 22)  Osmium
 * 23)   Iridium
 * 24)  Platinum
 * 25)  Gold (Level 3)
 * 26)  Mercury (element)
 * 27)  Thallium
 * 28)  Lead
 * 29)  Bismuth
 * 30)  Polonium
 * 31)  Astatine
 * 32)   Radon


 * 1)  Francium
 * 2)  Radium
 * 3)  Actinium
 * 4)  Thorium
 * 5)  Protactinium
 * 6)   Uranium
 * 7)  Neptunium
 * 8)  Plutonium
 * 9)  Americium
 * 10)  Curium
 * 11)  Berkelium
 * 12)  Californium

Chemical compounds: General

 * 1)  Chemical compound (Level 3)
 * 2)  Inorganic compound
 * 3)  Organic compound

Inorganic compounds

 * 1)   Water (Level 2)
 * 2)  Properties of water
 * 3)  Ice
 * 4)  Water vapor
 * 5)  Oxide
 * 6)   Carbon dioxide (Level 3)
 * 7)  Carbon monoxide
 * 8)  Nitrous oxide
 * 9)  Titanium dioxide
 * 10)   Hydrogen peroxide
 * 11)  Cyanide
 * 12)  Acid
 * 13)  Boric acid
 * 14)   Hydrochloric acid
 * 15)  Hydrofluoric acid
 * 16)  Nitric acid
 * 17)  Phosphoric acid
 * 18)  Sulfuric acid
 * 19)  Base
 * 20)   Ammonia
 * 21)  Potassium hydroxide
 * 22)   Sodium hydroxide

Salts

 * 1)  Salt (chemistry)
 * 2)  Carbonate
 * 3)  Calcium carbonate
 * 4)  Sodium bicarbonate
 * 5)  Sodium carbonate
 * 6)  Chloride
 * 7)   Calcium chloride
 * 8)  Polyvinyl chloride
 * 9)  Sodium chloride
 * 10)  Nitrate
 * 11)  Ammonium nitrate
 * 12)  Potassium nitrate
 * 13)  Sodium nitrate
 * 14)  Silicate
 * 15)  Sodium silicate
 * 16)  Sulfate
 * 17)  Alum
 * 18)   Sodium sulfate
 * 19)  Ammonium sulfate
 * 20)  Magnesium sulfate

Organic compounds

 * 1)  Haloalkane
 * 2)  Organophosphorus chemistry
 * 3)  Organosilicon chemistry
 * 4)  Silicone
 * 5)  Organosulfur chemistry
 * 6)  Thiol

Carbon–nitrogen bond

 * 1)  Amide
 * 2)  Urea
 * 3)  Nylon
 * 4)  Amine

Carbon–oxygen bond

 * 1)  Alcohol
 * 2)   Ethanol
 * 3)  Methanol
 * 4)  Aldehyde
 * 5)  Formaldehyde
 * 6)  Carboxylic acid
 * 7)  Acetic acid
 * 8)  Citric acid
 * 9)  Lactic acid
 * 10)  Ester
 * 11)  Polyester
 * 12)  Ether
 * 13)  Ketone
 * 14)  Acetone
 * 15)  Phenol
 * 16)  Tannin

Hydrocarbons

 * 1)  Hydrocarbon
 * 2)  Alkane
 * 3)  Butane
 * 4)  Ethane
 * 5)  Methane
 * 6)  Propane
 * 7)  Alkene
 * 8)  Ethylene
 * 9)  Polyethylene
 * 10)  Propylene
 * 11)  Polypropylene
 * 12)  Aromatic compound
 * 13)   Benzene
 * 14)  Alkyne

Chemical mixtures: General

 * 1)  Alloy (Level 3)
 * 2)  Mixture
 * 3)  Aerosol
 * 4)  Amalgam
 * 5)  Colloid
 * 6)  Dispersion
 * 7)  Emulsion
 * 8)  Foam
 * 9)  Gel
 * 10)  Solution
 * 11)  Suspension
 * 12)  Syngas

Specific alloys

 * 1)  Brass
 * 2)  Bronze (Level 3)
 * 3)  Cast iron
 * 4)  Steel (Level 3)
 * 5)  Stainless steel
 * 6)  Wrought iron

Earth science

 * For specific geographical places, see: Geography.

Basics

 * 1)  Earth science (Level 3)
 * 2)  Natural resource

Natural disasters

 * 1)  Natural disaster
 * 2)  Earthquake (Level 3)
 * 3)  Flood (Level 3)
 * 4)  Drought
 * 5)  Avalanche
 * 6)  Landslide
 * 7)   Tsunami
 * 8)   Wildfire

Earth: General

 * 1)  Internal structure of Earth (Level 3)

Geology

 * 1)  Geology (Level 2)
 * 2)   Plate tectonics (Level 3)
 * 3)  Fold
 * 4)  Stratigraphic unit
 * 5)  Meteorite
 * 6)  Impact crater
 * 7)  Lithosphere
 * 8)  Crust
 * 9)  Fault
 * 10)  Stratigraphy
 * 11)  Thrust fault

Mineralogy

 * 1)  Mineral (Level 3)
 * 2)  Mineralogy
 * 3)  Gemstone
 * 4)  Feldspar
 * 5)  Kaolinite
 * 6)  Pyroxene
 * 7)  Quartz
 * 8)  Talc
 * 9)  Mica
 * 10)  Gypsum
 * 11)  Asbestos

Mineral gemstones

 * 1)  Emerald
 * 2)  Jade
 * 3)  Sapphire
 * 4)  Ruby

Organic gemstones

 * 1)  Amber
 * 2)  Ivory
 * 3)  Pearl

Petrology

 * 1)  Petrology
 * 2)  Rock (Level 3)
 * 3)  Ore
 * 4)  Igneous rock
 * 5)  Basalt
 * 6)  Granite
 * 7)  Magma
 * 8)  Tuff
 * 9)  Sedimentary rock
 * 10)  Limestone
 * 11)  Clay
 * 12)  Sand
 * 13)   Oil shale
 * 14)  Sandstone
 * 15)  Bauxite
 * 16)  Metamorphic rock
 * 17)  Schist
 * 18)  Marble
 * 19)  Gneiss
 * 20)  Slate
 * 21)  Conglomerate
 * 22)  Breccia
 * 23)  Gravel

Geophysics

 * 1)  Geodesy
 * 2)  Geophysics
 * 3)  Earth's inner core
 * 4)  Earth's magnetic field
 * 5)  Earth's outer core
 * 6)  Mantle
 * 7)  Seismology

Geomorphology

 * 1)  Geomorphology
 * 2)  Erosion (Level 3)
 * 3)  Weathering

Landforms

 * 1)  Landform
 * 2)  Land (Level 2)
 * 3)  Continent (Level 3)
 * 4)  Mountain (Level 3)
 * 5)  Mountain range
 * 6)  Hill
 * 7)  Valley
 * 8)  Plateau
 * 9)  Mesa
 * 10)  Plain
 * 11)  Sedimentary basin

Fluvial landforms

 * 1)  Alluvial fan
 * 2)  Beach
 * 3)  Canyon
 * 4)  Cliff
 * 5)  Floodplain
 * 6)  Meander
 * 7)  Oasis
 * 8)  Rapids
 * 9)  Waterfall

Glacial landforms

 * 1)  Glacial landform
 * 2)  Fjord
 * 3)  Moraine

Caves

 * 1)  Cave
 * 2)  Karst

Oceanic and coastal landforms

 * 1)  Abyssal plain
 * 2)  Archipelago
 * 3)  Bay
 * 4)  Coast
 * 5)  Continental shelf
 * 6)  Coral reef
 * 7)  Atoll
 * 8)  Lagoon
 * 9)  Oceanic trench
 * 10)  Peninsula
 * 11)  Island (Level 3)
 * 12)  Seamount

Volcanic landforms

 * 1)   Volcano (Level 3)
 * 2)   Geyser
 * 3)  Hotspot
 * 4)  Lava
 * 5)  Mid-ocean ridge

Aeolian landforms

 * 1)  Aeolian processes
 * 2)  Dune

Artificial landforms

 * 1)  Artificial island
 * 2)  Land reclamation
 * 3)  Polder

Geological history

 * 1)  History of Earth (Level 3)
 * 2)   Geological history of Earth
 * 3)  Geochronology
 * 4)   Geologic time scale
 * 5)  Great Oxidation Event
 * 6)  Cambrian explosion
 * 7)  Extinction event
 * 8)  Late Ordovician mass extinction
 * 9)  Late Devonian extinction
 * 10)  Permian–Triassic extinction event
 * 11)  Triassic–Jurassic extinction event
 * 12)  Cretaceous–Paleogene extinction event
 * 13)  Ice age
 * 14)  Pangaea

Geological periods

 * 1)  Precambrian
 * 2)  Phanerozoic
 * 3)  Paleozoic
 * 4)  Cambrian
 * 5)  Permian
 * 6)  Mesozoic
 * 7)  Triassic
 * 8)  Jurassic
 * 9)  Cretaceous
 * 10)  Cenozoic
 * 11)  Paleogene
 * 12)  Neogene
 * 13)  Quaternary
 * 14)  Holocene

Biomes

 * 1)  Desert (Level 3)
 * 2)  Tundra
 * 3)  Shrubland

Forests

 * 1)  Forest (Level 3)
 * 2)  Jungle
 * 3)  Mangrove
 * 4)  Taiga
 * 5)  Rainforest
 * 6)  Tropical rainforest
 * 7)  Temperate broadleaf and mixed forests

Grasslands

 * 1)  Grassland (Level 3)
 * 2)  Meadow
 * 3)  Prairie
 * 4)  Savanna
 * 5)  Steppe

Wetlands

 * 1)  Wetland
 * 2)  Swamp
 * 3)  Marsh
 * 4)  Bog

Pedology

 * 1)  Soil (Level 3)
 * 2)  Peat
 * 3)  Soil formation
 * 4)  Pedosphere
 * 5)  Sediment
 * 6)  Soil fertility
 * 7)  Soil science

Atmosphere

 * 1)  Atmosphere of Earth (Level 3)
 * 2)  Air mass
 * 3)  Atmospheric pressure
 * 4)  Atmospheric science
 * 5)  Ozone depletion

Atmospheric optics

 * 1)  Aurora
 * 2)  Mirage
 * 3)   Rainbow
 * 4)  Sky

Climatology

 * 1)  Climatology
 * 2)  Climate (Level 2)
 * 3)  Climate change (Level 3)
 * 4)  Greenhouse effect
 * 5)   Climate variability and change
 * 6)  El Niño–Southern Oscillation
 * 7)  Köppen climate classification
 * 8)  Temperate climate
 * 9)  Tropical climate

Meteorology: General

 * 1)  Meteorology
 * 2)  Weather (Level 3)
 * 3)  Weather front
 * 4)  Weather forecasting
 * 5)  Humidity
 * 6)  Low-pressure area

Clouds

 * 1)  Cloud (Level 3)
 * 2)  Cirrus cloud
 * 3)  Cumulonimbus cloud
 * 4)  Cumulus cloud
 * 5)  Fog

Precipitation

 * 1)  Precipitation
 * 2)  Rain (Level 3)
 * 3)  Snow (Level 3)
 * 4)  Acid rain
 * 5)  Hail
 * 6)  Dew
 * 7)  Frost

Seasons

 * 1)  Season (Level 3)
 * 2)  Spring (season)
 * 3)  Summer
 * 4)  Autumn
 * 5)  Winter

Atmospheric circulation

 * 1)  Atmospheric circulation
 * 2)  Anticyclone
 * 3)  Cyclone
 * 4)   Extratropical cyclone
 * 5)  Hadley cell
 * 6)  Polar vortex
 * 7)  Walker circulation

Storms

 * 1)  Storm
 * 2)   Tornado (Level 3)
 * 3)   Tropical cyclone (Level 3)
 * 4)  Blizzard
 * 5)  Dust storm
 * 6)  Lightning
 * 7)  Thunderstorm

Winds

 * 1)   Wind (Level 3)
 * 2)  Jet stream
 * 3)  Monsoon
 * 4)  Trade winds

Water: General

 * 1)  Hydrosphere
 * 2)  Cryosphere

Glaciology

 * 1)   Glacier (Level 3)
 * 2)  Ice sheet
 * 3)  Ice shelf
 * 4)  Iceberg
 * 5)  Sea ice
 * 6)  Permafrost

Oceanography

 * 1)  Oceanography
 * 2)  Sea (Level 2)
 * 3)  Ocean
 * 4)  Tide
 * 5)  Sea level
 * 6)  Seabed
 * 7)  Ocean current
 * 8)  Thermohaline circulation

Hydrology

 * 1)  Hydrology
 * 2)   Water cycle
 * 3)  Groundwater
 * 4)  Spring (hydrology)
 * 5)  Hydrography
 * 6)  Limnology
 * 7)  Lake (Level 3)
 * 8)  Dry lake
 * 9)  Pond
 * 10)  River (Level 3)
 * 11)  Drainage basin
 * 12)  Estuary
 * 13)  River delta

Basics

 * 1)   Physics (Level 2)
 * 2)  Energy (Level 2)
 * 3)  Conservation of energy
 * 4)  Matter (Level 3)
 * 5)   Atom (Level 2)
 * 6)  Force (Level 3)
 * 7)  Electromagnetism (Level 3)
 * 8)  Gravity (Level 3)
 * 9)  Strong interaction (Level 3)
 * 10)  Weak interaction (Level 3)
 * 11)  Spacetime
 * 12)  Space (Level 3)
 * 13)  Vacuum (Level 3)
 * 14)  Time (Level 2)
 * 15)  Mass–energy equivalence
 * 16)  Quantum gravity
 * 17)  Radiation
 * 18)  Ionizing radiation
 * 19)  Field (physics)
 * 20)  Flux
 * 21)  Gauge theory
 * 22)  Symmetry (physics)
 * 23)  Theoretical physics

Atomic physics

 * 1)  Atomic physics
 * 2)  Atomic nucleus
 * 3)  Atomic orbital
 * 4)  History of atomic theory
 * 5)  Binding energy
 * 6)  Bohr model
 * 7)  Bremsstrahlung
 * 8)  Electron configuration
 * 9)  Electron shell
 * 10)  Energy level
 * 11)  Rutherford scattering experiments
 * 12)  Ion
 * 13)  Isotope

Molecular physics

 * 1)  Molecular orbital
 * 2)  Molecular orbital theory

Optics

 * 1)  Optics (Level 3)
 * 2)  Focus
 * 3)  Focal length
 * 4)  Polarization
 * 5)  Reflection
 * 6)  Refraction
 * 7)  Refractive index
 * 8)  Transparency and translucency

Basics

 * 1)  Color (Level 3)
 * 2)  CMYK color model
 * 3)  Color theory
 * 4)  Primary color
 * 5)  Gloss (optics)
 * 6)  RGB color model

Color terms

 * 1)  White
 * 2)  Black
 * 3)  Grey
 * 4)  Red
 * 5)  Orange
 * 6)  Yellow
 * 7)   Green
 * 8)  Blue
 * 9)  Pink
 * 10)  Purple
 * 11)  Brown

Basics

 * 1)  Condensed matter physics
 * 2)  Solid-state physics
 * 3)  Amorphous solid

Crystallography

 * 1)  Crystallography
 * 2)  Crystal
 * 3)  Crystallization

States of matter

 * 1)  State of matter (Level 3)
 * 2)  Solid
 * 3)  Liquid
 * 4)  Gas
 * 5)  Vapor
 * 6)   Plasma
 * 7)  Degenerate matter
 * 8)  Bose–Einstein condensate

Phase transitions

 * 1)  Phase transition
 * 2)  Phase
 * 3)  Boiling
 * 4)  Melting
 * 5)  Freezing
 * 6)  Evaporation
 * 7)  Condensation
 * 8)  Ionization
 * 9)  Sublimation
 * 10)  Critical point
 * 11)  Triple point

Basics

 * 1)  Electricity (Level 2)
 * 2)  Magnetism (Level 3)
 * 3)  Ferromagnetism
 * 4)  Magnet
 * 5)  Electromagnet
 * 6)  Dielectric
 * 7)  Dipole
 * 8)  Metamaterial
 * 9)  Oil drop experiment
 * 10)  Photoelectric effect

Electrostatics

 * 1)  Electrostatics
 * 2)  Coulomb's law
 * 3)  Electric charge
 * 4)  Electric field
 * 5)  Electric potential

Electrodynamics

 * 1)  Electromagnetic radiation (Level 3)
 * 2)  Electromagnetic spectrum
 * 3)  Radio wave
 * 4)  Microwave
 * 5)  Infrared
 * 6)  Visible spectrum
 * 7)   Ultraviolet
 * 8)  X-ray
 * 9)  Fluorescence
 * 10)  Electromagnetic field
 * 11)  Electromagnetic induction
 * 12)  Electromotive force
 * 13)  Lorentz force
 * 14)  Eddy current
 * 15)  Maxwell's equations

Magnetism

 * 1)  Magnetic field
 * 2)  Magnetostatics

Electrical circuits

 * 1)  Electric current
 * 2)  Alternating current
 * 3)  Direct current
 * 4)  Electrical network
 * 5)  Electrical impedance
 * 6)  Electrical resistance and conductance
 * 7)  Ohm's law
 * 8)  Capacitance
 * 9)  Semiconductor
 * 10)   Superconductivity
 * 11)  Gain (electronics)
 * 12)  Inductance
 * 13)  Kirchhoff's circuit laws

Basics

 * 1)  Mechanics
 * 2)  Ballistics
 * 3)  Continuum mechanics
 * 4)  Kinematics
 * 5)  Relativistic mechanics
 * 6)  Statics
 * 7)  Oscillation
 * 8)  Harmonic oscillator
 * 9)  Simple harmonic motion

Quantum mechanics

 * 1)   Quantum mechanics (Level 3)
 * 2)  Pauli exclusion principle
 * 3)  Quantum chromodynamics
 * 4)  Quantum electrodynamics
 * 5)  Quantum entanglement
 * 6)  Quantum field theory
 * 7)  Quantum tunnelling
 * 8)   Schrödinger equation
 * 9)  Uncertainty principle
 * 10)  Wave function
 * 11)  Wave–particle duality

Classical mechanics

 * 1)  Classical mechanics (Level 3)
 * 2)  Hamiltonian mechanics
 * 3)  Lagrangian mechanics
 * 4)  Mass (Level 3)
 * 5)  Density
 * 6)  Momentum (Level 3)
 * 7)  Motion (Level 3)
 * 8)  Newton's laws of motion (Level 3)
 * 9)  Speed
 * 10)  Acceleration
 * 11)  Velocity
 * 12)  Equations of motion
 * 13)  Kinetic energy
 * 14)  Potential energy
 * 15)  Inertia
 * 16)  Moment of inertia
 * 17)  Friction
 * 18)  Impulse
 * 19)  Power
 * 20)  Work
 * 21)  Rotation
 * 22)  Angular momentum
 * 23)  Centripetal force
 * 24)  Coriolis force
 * 25)  Torque
 * 26)  Weight
 * 27)  Weighing scale
 * 28)  Frame of reference
 * 29)  Newton's law of universal gravitation

Fluid mechanics

 * 1)  Fluid mechanics
 * 2)  Fluid dynamics
 * 3)  Aerodynamics
 * 4)  Bernoulli's principle
 * 5)  Buoyancy
 * 6)  Convection
 * 7)  Drag
 * 8)  Diffusion
 * 9)  Flight
 * 10)  Lift (force)
 * 11)  Navier–Stokes equations
 * 12)  Osmosis
 * 13)  Reynolds number
 * 14)   Surface tension
 * 15)  Turbulence
 * 16)  Viscosity

Solid mechanics

 * 1)  Solid mechanics
 * 2)  Deformation
 * 3)  Elastic modulus
 * 4)  Elasticity
 * 5)  Fatigue
 * 6)  Hooke's law
 * 7)  Plasticity
 * 8)  Stiffness
 * 9)  Strength of materials
 * 10)  Stress (mechanics)

Statistical mechanics

 * 1)  Statistical mechanics

Nuclear physics

 * 1)  Nuclear physics
 * 2)  Nuclear fission
 * 3)  Nuclear fusion
 * 4)  Nucleosynthesis
 * 5)  Radioactive decay (Level 3)
 * 6)  Alpha particle
 * 7)  Beta particle
 * 8)  Gamma ray

Particle physics: General

 * 1)  Particle physics (Level 3)
 * 2)  Standard Model (Level 3)
 * 3)  Physics beyond the Standard Model
 * 4)   String theory
 * 5)  Supersymmetry
 * 6)  Particle
 * 7)  Particle accelerator
 * 8)  Large Hadron Collider
 * 9)  Tevatron
 * 10)  Particle detector
 * 11)  Cloud chamber
 * 12)  Scattering
 * 13)  Spin

Subatomic particles

 * 1)  Subatomic particle (Level 3)

Fermions

 * 1)  Fermion
 * 2)  Lepton
 * 3)  Electron (Level 3)
 * 4)  Muon
 * 5)  Tau
 * 6)  Neutrino
 * 7)  Quark
 * 8)  Hadron
 * 9)  Baryon
 * 10)  Neutron (Level 3)
 * 11)  Proton (Level 3)
 * 12)  Meson

Bosons

 * 1)  Boson
 * 2)  Gauge boson
 * 3)   Photon (Level 3)
 * 4)  Gluon
 * 5)  W and Z bosons
 * 6)  Higgs boson

Antimatter

 * 1)  Antimatter
 * 2)  Antiparticle
 * 3)  Positron

Theory of relativity

 * 1)  Theory of relativity (Level 3)
 * 2)  General relativity
 * 3)   Special relativity
 * 4)  Principle of relativity
 * 5)  Equivalence principle
 * 6)  Gravitational wave
 * 7)  Lorentz transformation
 * 8)  Michelson–Morley experiment

Thermodynamics

 * 1)   Thermodynamics (Level 3)
 * 2)  Heat (Level 3)
 * 3)  Temperature (Level 3)
 * 4)  Absolute zero
 * 5)  Pressure
 * 6)  Laws of thermodynamics
 * 7)  Heat capacity
 * 8)  Heat transfer
 * 9)   Entropy
 * 10)  Enthalpy
 * 11)  Black-body radiation
 * 12)  Internal energy
 * 13)  Thermodynamic cycle
 * 14)  Thermodynamic free energy
 * 15)  Ideal gas law

Waves

 * 1)  Wave (Level 3)
 * 2)  Light (Level 3)
 * 3)  Speed of light (Level 3)
 * 4)  Acoustics
 * 5)   Sound (Level 3)
 * 6)  Speed of sound
 * 7)  Ultrasound
 * 8)  Amplitude
 * 9)  Frequency
 * 10)  Wavelength
 * 11)  Diffraction
 * 12)  Doppler effect
 * 13)  Wave interference
 * 14)  Noise
 * 15)  Resonance
 * 16)  Superposition principle
 * 17)  Wave equation