Astrophysics (index)about


(measure of heat in matter)

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.


Referenced by:
Abiotic Oxygen
Absorption Line
Adiabatic Process
Asymptotic Giant Branch (AGB)
Adaptive Mesh Refinement (AMR)
Antenna Temperature
Atmospheric Temperature Profile
Balmer Jump
Beta (β)
Binding Energy
Black Body (BB)
Black-Body Radiation
Boltzmann Constant (k)
Boltzmann Equation
Bose-Einstein Statistics
Carbonate-Silicate Cycle
Carbonate System
Chemical Equilibrium (CE)
Cepheid Variable
CMB Polarization
CNO Cycle
Carbon Monoxide (CO)
Cold Gas
Cold Spot
Eccentricity (e)
Eclipse Mapping
Effective Temperature (Teff)
Reduction Potential (Eh)
Electron Degeneracy
Equation of State (EoS)
Equilibrium Condensation Model
Equilibrium Temperature (Teq)
Ethylene (C2H4)
55 Cancri e (55 Cnc e)
Galaxy Formation
Gamow Peak
Gravitational Collapse
Greenhouse Effect
Horizontal Branch (HB)
Acetylene (C2H2)
Helium (He)
HII Region (HII)
Infrared (IR)
Instability Strip
Isothermal Core
Jeans Length
Kinetic Energy
Kelvin-Helmholtz Mechanism
Kramers' Opacity Law
Line Shape Function
Lithium (Li)
Local Thermodynamic Equilibrium (LTE)
Magma Ocean
Maxwell-Boltzmann Distribution
M-Type Star (M)
Mean Free Path
Meridional Flow
Mixing Length Theory
Molecular Cloud
Noise Temperature
Nuclear Energy Generation Rate (ε)
Partition Function (Z)
Partial Differential Equation (PDE)
Phase Transition
Planck Function
Planet Formation
Power Law
Protoplanetary Nebula (PPN)
Quantum Tunneling
Radioactive Dating
Refractory Material
Reynolds Number (Re)
Saha Equation
Schönberg-Chandrasekhar Limit
Shock Wave
Spectral Line Energy Distribution (SLED)
Superluminous Supernova (SLSN)
Snow Line
Solar Wind
Specific Heat
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
Superionic Ice
Surface Temperature
Sachs-Wolfe Effect (SWE)
Sunyaev-Zel'dovich Effect (SZ Effect)
Transition Edge Sensor (TES)
Thermal Noise
Thermal Wind
Thermodynamic Equilibrium (TE)
Tillotson Equation
Water Vapor Planet
White Dwarf
Wien's Displacement Law