(measurement of light with various electromagnetic wavelengths)
Spectroscopy (or spectrometry) is the study of radiation
intensity as a
function of wavelength. It is the method for determining the
chemical composition of astronomical bodies as well as temperature
and radial velocity.
Spectrography is virtually the same study.
Instruments operating at or near visible light typically use prisms or
gratings that angle light according to wavelength (dispersion).
Dispersion with prisms is small so often multiple prisms are used in
tandem, e.g., a triple prism spectrograph.
Photometry is like an extremely-low-resolution spectroscopy,
studying stars and astronomical bodies based upon just a few
passbands. Its advantage is that it requires much less electromagnetic radiation,
thus can be used for more distant objects, and is also
multi-object by default.
Some instrument terms/classes:
Intensity at each wavelength is typically the quality of interest
but there are also cases when polarization at each wavelength
is the quality of interest.
Referenced by pages:
Baryon Oscillation Spectroscopic Survey (BOSS)
cavity-enhanced absorption spectroscopy (CEAS)
Chandra X-ray Observatory (CXO)
Carnegie Supernova Project (CSP)
Lowell Discovery Telescope (LDT)
velocity dispersion (σ)
exoplanet eclipse light curve
ESO Nearby Abell Cluster Survey (ENACS)
51 Eridani b
Gran Telescopio Canarias (GTC)
imaging Fourier transform spectroscopy (IFTS)
integral field spectrograph
Multi-Epoch Nearby Cluster Survey (MENeaCS)
Nearby Supernova Factory (NSNF)
Rossiter-McLaughlin effect (RM effect)
radial velocity method
Supernova Cosmology Project (SCP)
signatures of formation
chromospheric activity index
6dF Galaxy Survey (6dFGS)
spectral line designation
stellar parameter determination
stellar temperature determination
2dF Galaxy Redshift Survey (2dFGRS)
VLT-FLAMES Tarantula Survey (VFTS)
James Webb Space Telescope (JWST)
William Herschel Telescope (WHT)