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**Temperature** is the measure of hotness or coldness of
something, which corresponds to the kinetic energy of
the random motion of its constituent particles.
In daily life, temperature is fairly clear, but
a cited temperature may need qualification for
some extreme conditions, regarding how it is determined,
or when describing something where temperature is
varying in time or space. Some means by which temperature
is measured:

**Excitation temperature**is based upon the degree of excitation of the particles (atoms) and is defined by using the Boltzmann constant and Boltzmann equation that describes the relation of temperature to states of excitation, e.g., electrons above their ground state.**Ionization temperature**is similar for the degree of ionization, using the Saha equation.- Effective temperature is the temperature of a black body that would produce the same total electromagnetic radiation as a star or other object is producing.
**Color temperature**(in astronomy) is the temperature of a black body that would match a range of a star's (or other object's) spectrum. More specifically, the term may be used for a temperature value based on photometry.**Kinetic temperature**reflects the kinetic energy of a material's molecules, i.e., regarding the speed of the molecules but not their molecular rotation and vibration. It is defined as 2/3 the Boltzmann constant times the mean kinetic energy of the molecules.

Stellar temperature determination is accomplished using these values and others.

abiotic oxygen

absorption

absorption line

A-type star (A)

adiabatic process

asymptotic giant branch (AGB)

adaptive mesh refinement (AMR)

angular power spectrum

anisotropy

antenna temperature

ARCADE

atmosphere

atmospheric escape

atmospheric temperature profile

Balmer jump

baroclinicity

Big Bang nucleosynthesis (BBN)

B-type star (B)

beta (β)

binding energy

black body (BB)

black-body radiation

bolometer

bolometric correction

Boltzmann constant (k)

Boltzmann equation

Bose-Einstein statistics

carbonate-silicate cycle

carbonate system

CCAT-prime (CCAT-p)

chemical equilibrium (CE)

Cepheid variable (CEP)

chemodynamics

clathrate

CMB polarization

CNO cycle

carbon monoxide (CO)

cold gas

cold spot

comet

cooling function

cryovolcano

data cube

deuterium burning

Earth

earthshine

eccentricity (

eclipse mapping

effective temperature (T

reduction potential (Eh)

electron capture

electron degeneracy

emissivity

entropy (S)

equation of state (EoS)

equilibrium condensation model

equilibrium temperature (T

ethylene (C

exosphere

55 Cancri e (55 Cnc e)

51 Eridani b

fractionation

fusion

galaxy formation

Gamow peak

giant star

gravitational collapse

greenhouse effect

habitability

Hadley cell

horizontal branch (HB)

acetylene (C

helium (He)

neutral atomic hydrogen (HI)

HII region (HII)

HI region (HI)

homologous collapse

HR 8799

H-R diagram (HRD)

humidity

hydrodynamic escape

hydrology

ice giant

ionization correction factor (ICF)

infrared (IR)

insolation

instability strip

integration time

Io

isothermal core

Jeans escape

Jeans length

kappa mechanism (κ-mechanism)

kinetic energy (KE)

Kelvin-Helmholtz mechanism

K-line

Kramers opacity law

potassium/thorium ratio (K/Th ratio)

line shape function

lithium (Li)

local thermodynamic equilibrium (LTE)

magma ocean

Mars

mathematical field

Maxwell-Boltzmann distribution

M-type star (M)

mean free path

meridional flow

mixing length theory

molecular cloud

noise temperature

nuclear energy generation rate (ε)

O5 spectral class (O5)

O-type star (O)

Origins Space Telescope (OST)

partition function (Z)

partial differential equation (PDE)

pointing error (PE)

phase transition

photosphere

Planck function

planet formation

planet type

plasma

power law

proton-proton chain

protoplanetary nebula (PPN)

protoplanetary disk (PPD)

quantum tunneling

radioactive dating

Rayleigh-Jeans law

red clump (RC)

red giant

refractory material

retrieval

Reynolds number (Re)

Saha equation

scale height (H)

Schönberg-Chandrasekhar limit

spectral energy distribution (SED)

shock wave

siderophile

sigma (σ)

silicon (Si)

spectral line energy distribution (SLED)

superluminous supernova (SLSN)

snow line

solar wind

specific heat

spectral class

spectral index (α)

spectral signature

spectroscopy

star formation (SF)

state of excitation

state of ionization

Stefan-Boltzmann constant (σ)

stellar core

stellar model atmosphere

stellar parameter determination

stellar radius determination

stellar structure

stellar temperature determination

stratigraphy

Strömgren sphere

supercooling

supergiant

superionic ice

surface temperature

Sachs-Wolfe effect (SWE)

symmetry breaking

Sunyaev-Zel'dovich effect (SZ effect)

transition edge sensor (TES)

thermal noise

thermal runaway

thermal wind

thermodynamic equilibrium (TE)

tidal locking

Tillotson equation

Titan

ultraluminous infrared galaxy (ULIRG)

Vega

virial theorem

volatile material

water activity (a

water vapor planet

weathering

wavefront error (WFE)

white dwarf

Wien's displacement law

WISE 0855-0714

zonal flow