Astrophysics (Index)About

spectroscopy

(measurement of light with various electromagnetic wavelengths)

Spectroscopy (or spectrometry or spectrography) is the study of electromagnetic radiation (EMR) 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 and other characteristics. The overall shape of the spectrum is of interest, such as its resemblance to a black-body spectrum, and spectral lines and their spectral line shapes are also revealing.

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 something 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 EMR, thus can be used for more distant objects, and is also multi-object by default. Some spectroscopy 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 (spectropolarimetry). Other terms for various branches of spectroscopy:


Note that the same terms are also sometimes used for analogous analysis of quantities other than EMR-wavelength, perhaps most often using the word spectrography. Examples are the mass or kinetic energy of some source of particles (e.g., the term mass spectrometer).


(science,measurement,astronomy,color,EMR)
Further reading:
https://en.wikipedia.org/wiki/Astronomical_spectroscopy
https://en.wikipedia.org/wiki/Spectroscopy
https://astronomy.swin.edu.au/cosmos/s/Spectroscopy
https://imagine.gsfc.nasa.gov/science/toolbox/spectra1.html
https://webbtelescope.org/contents/articles/spectroscopy-101--introduction.html
http://astronomy.nmsu.edu/cwc/Teaching/ASTR605/Lectures/spectra.pdf
https://sites.astro.caltech.edu/~george/ay122/Ay122a_Spectroscopy.pdf
https://ui.adsabs.harvard.edu/abs/2013pss2.book...35M/abstract

Referenced by pages:
2dF Galaxy Redshift Survey (2dFGRS)
51 Eridani b
6dF Galaxy Survey (6dFGS)
absorption
abundances
ASPECS
atmosphere
Baryon Oscillation Spectroscopic Survey (BOSS)
BASS
BCool
Carnegie Supernova Project (CSP)
cavity-enhanced absorption spectroscopy (CEAS)
Chandra X-ray Observatory (CXO)
chromospheric activity index
color index
cryogenic spectroscopy
CubIXSS
cyclotron radiation emission spectroscopy (CRES)
differential spectroscopy
earthshine
electron shell
ELM Survey
emission
ESO Nearby Abell Cluster Survey (ENACS)
exoplanet eclipse light curve
exosatellite
eXTP
Faint Infrared Grism Survey (FIGS)
FINESSE
forward model
Gaia
GAMA
Gemini Observatory
Gran Telescopio Canarias (GTC)
grism
ground state
H-alpha (Ha)
H3 Survey (H3)
HBK
HCI
HRS
imaging Fourier transform spectroscopy (IFTS)
imaging spectrometer
immersion grating
integral field spectrograph
integral field unit (IFU)
IRAS
James Webb Space Telescope (JWST)
Kirchhoff's laws
LAMBDA
LAMOST
line blanketing
Lowell Discovery Telescope (LDT)
methylidyne (CH)
Mimir
Multi-Epoch Nearby Cluster Survey (MENeaCS)
Nearby Supernova Factory (NSNF)
neutron scattering
NEWS
NICER
OSO 8
photometry
RADEX
radial velocity method
radioactive decay
relativistic effect
RESOLVE­
Rossiter-McLaughlin effect (RM effect)
SAGE
secondary eclipse
signatures of formation
spectral line designation
spectrography
spectrometry
spectroscope
SPICA
stellar parameter determination
stellar temperature determination
Supernova Cosmology Project (SCP)
synthetic photometry
telluric star
transit spectroscopy
transmission spectroscopy
velocity dispersion (σ)
Venus Express
VERITAS
VLT-FLAMES Tarantula Survey (VFTS)
William Herschel Telescope (WHT)
XMM-Newton
XRISM

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