Menu
Home Explore People Places Arts History Plants & Animals Science Life & Culture Technology

Observational astronomy

Absolute magnitude
Measure of the luminosity of celestial objects
Air mass (astronomy)
The amount of air seen through in astronomical observations
Airglow
Faint emission of light by a planetary atmosphere
Angular diameter
How large a sphere or circle appears
Angular resolution
Ability of any image-forming device to distinguish small details of an object
Apparent magnitude
Brightness of a celestial object observed from the Earth
Astrometry
Branch of astronomy involving positioning and movements of celestial bodies
Astronomical radio source
Object in outer space that emits strong radio waves
Astronomical seeing
Amount of apparent blurring and twinkling of astronomical objects due to atmospherical effects
Astronomical spectroscopy
Science of temporal, spatial, and spectral distributions of radiation
Astrophysical maser
Naturally occurring source of stimulated spectral line emission, typically in the microwave portion of the electromagnetic spectrum
Astrophysical X-ray source
Astronomical object emitting X-rays
Bortle scale
A scale of night sky brightness.
Brightness temperature
Temperature associated with the measured intensity and frequency
Cosmic distance ladder
Succession of methods by which astronomers determine the distances to celestial objects
Effective temperature
Estimated temperature of an astronomical body
Extinction (astronomy)
In astronomy, the absorption and scattering of electromagnetic radiation by dust and gas between an emitting astronomical object and the observer
Forbidden mechanism
Spectral line associated with absorption or emission of light by atomic nuclei, atoms, or molecules
Gamma-ray astronomy
Observational astronomy performed with gamma rays
High-energy astronomy
Study of astronomical objects that release ionizing radiation of highly energetic wavelengths
Infrared astronomy
Observational astronomy of emissions over the wavelength band 0.75 to 300 micrometers
Light curve
Graph of light intensity of a celestial object or region, as a function of time
Luminosity
Measurement of radiant electromagnetic power emitted by an object
Luminosity distance
Astronomical measurand
Magnitude (astronomy)
Logarithmic measure of the brightness of an astronomical object
Megamaser
Type of astrophysical maser with large isotropic luminosity
Observatory
Location used for observing terrestrial or celestial events
Photometric system
Set of well-defined passbands (or filters), with a known sensitivity to incident radiation
Photometry (astronomy)
Determination of light intensities of astronomical bodies
Planetary nebula luminosity function
Astronomical function
Polarization in astronomy
Proper motion
Astronomical measure of the observed changes in the apparent places of stars in the sky
Radial velocity
Velocity of an object as the rate of distance change between the object and a point
Radio astronomy
Subfield of astronomy that studies celestial objects at radio frequencies
Radio spectrum pollution
Deviation of radio waves beyond allocations
Recessional velocity
The rate at which an astronomical object becomes more distant from an observer
Sky brightness
Visual perception of the sky and how it scatters and diffuses light.
Spectral energy distribution
Topic in astronomy
Spectral index
Measure of the dependence of radiative flux density on frequency (astronomical term)
Stellar parallax
Apparent shift of position of a nearby star against the background of distant objects during Earth's orbital period
Submillimetre astronomy
Astronomy with terahertz (< 1 mm)-range light
Surface brightness
Measure of brightness of an astronomical object
Tip of the red-giant branch
Primary distance indicator used in astronomy
Twinkling
Variation in brightness and the position of stars due to atmospheric refraction
UBV photometric system
Wide-band photometric system used in astronomy
Ultraviolet astronomy
Observation of electromagnetic radiation at ultraviolet wavelengths
Vampire literature
Speculative literary genre
Visible-light astronomy
Encompasses a wide variety of astronomical observation via telescopes
X-ray astronomy
Branch of astronomy that uses X-ray observation