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visible light

(light)
(electromagnetic radiation, wavelength 390-750 nm)

Visible light (or light) is electromagnetic radiation (EMR) visible to us. Its wavelengths are in the range of 390 nm to 750 nm. It is situated between infrared and ultraviolet.

It is a tiny portion of the usable EMR spectrum and is a much smaller range than the other well-known categories (ultraviolet, radio, etc.). This small portion is of interest for matching our visual sense, which, in turn, makes use of the most intense portion of the Sun's spectrum that reaches us through Earth atmospheric windows.

The word optical is often used to indicate visible light when describing/name an astronomical survey, observation, instrument, or telescope, but is also commonly used for the portions of infrared and ultraviolet for which equipment (e.g., telescope mirrors) are identical or similar.

Visible light observation was the entirety of astronomy for millennia and it has only been in the 20th century that astronomy has encompassed more, beginning with the discovery of radio sources, and the use of visible-light telescopes to image the portions of the ultraviolet and infrared close to visible light. It is also the primary type of observation by amateur astronomers, and casual astronomical viewing. The night sky, with the pattern of movements of the stars, planets, Sun, and Moon were much of what astronomy constituted. Weather has always been a challenge to visible-light viewing and light pollution is now a serious challenge. Viewing from high altitudes offer advantages.


(EMR,spectrum,band)
http://en.wikipedia.org/wiki/Visible_light
WaveLFreqPhoton
Energy
  
390nm769THz3.2eVbeginvisible light
750nm400THz1.7eVendvisible light

Referenced by:
absorption
absorption coefficient
Atacama Cosmology Telescope (ACT)
active galaxy
active galactic nucleus (AGN)
Airy disk
albedo
angular magnification
angular resolution
antenna pattern
adaptive optics (AO)
aperture
aperture photometry
aperture synthesis
apodization
astronomical quantities
aurora
bar
biofluorescence
black body (BB)
BlackGEM
black hole (BH)
bolometric correction
bolometric magnitude (Mbol)
Large Altazimuth Telescope (BTA-6)
Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS)
Cassegrain reflector
cosmic background radiation (CBR)
CCD
Canada-France-Hawaii Telescope (CFHT)
Cherenkov radiation
cosmic infrared background (CIB)
cosmic optical background (COB)
coherent light
COLD GASS
collimator
Colossus Telescope
confusion limit
convolution
corona
coronagraph
cosmic dust
coudé focus telescope
Cerro Tololo Inter-American Observatory (CTIO)
curvature radiation
dark sky
Discovery Channel Telescope (DCT)
Dark Energy Survey (DES)
diffraction
Dragone telescope
earthshine
extragalactic background light (EBL)
exoplanet eclipse light curve
eclipsing binary (E)
effective radius (Re)
electromagnetic spectrum
elevation range
electromagnetism (EM)
emission
electromagnetic radiation (EMR)
epoch of reionization (EOR)
extremely red object (ERO)
European Southern Observatory Very Large Telescope (ESO VLT)
Euclid
extreme ultraviolet (EUV)
extreme adaptive optics (ExAO)
extinction
Faraday rotation
far infrared (FIR)
filter
fluorescence
focal plane array (FPA)
Fabry-Pérot interferometer (FPI)
FRB121102
frequency
Gaia
G band
G-CLEF
Gemini Observatory
geodesic
Giant Magellan Telescope (GMT)
Gould's Belt Distances Survey (GOBELINS)
GRANAT
grating
gravitational lensing
gravity
greenhouse effect
Gran Telescopio Canarias (GTC)
gravitational wave strain (h)
H-alpha (Ha)
Hawaii K-band Galaxy Survey
Hewitt & Burbidge Catalog (HB87)
HCI
helium 1083nm line
HERMES
Holmberg radius
Hubble Space Telescope (HST)
I band
imaging Fourier transform spectroscopy (IFTS)
integral field unit (IFU)
illumination
image stabilization
infrared (IR)
INTEGRAL
integral field spectrograph
interference
interferometer
interferometry
IOTA
IRTF
JUICE
Juno
K band
Keck Observatory
KID
Kramers opacity law
Lambda-CDM model (ΛCDM)
Large Binocular Telescope (LBT)
Las Cumbres Observatory (LCO)
light cone
light curve
light echo
light pollution
limb darkening
line blanketing
line broadening
Lorentz transformation
LUVOIR
light-year (ly)
Lyman-alpha forest
Lyot stop
Magellan Telescopes
magnitude
mass spectrometer
mass-to-light ratio (M/L)
Maxwell's equations
MeerLICHT
meteoroid
Michelson interferometer
gravitational microlensing
Mie scattering
MMX
moon
Multi-object Optical and Near-IR Spectrograph (MOONS)
MOST
multi-messenger astronomy
multi-object spectrograph
Nasmyth telescope
N-body simulation
near infrared (NIR)
Newtonian telescope
nitrogen (N)
New Technology Telescope (NTT)
observatory
occultation observations
occulting bar
OGLE
OH/IR source
OIR
Olbers' paradox
1 Jansky Empty Field Survey (1 Jy)
opacity (κ)
optical double
optical interferometer
optics
Orion Disks
OSO 7
PanCET
panchromatic
parsec (pc)
particle horizon
phase angle
photochemistry
photometry
photon
Pi of the Sky
plane-parallel atmosphere
polarization
polarization modes
Poynting-Robertson effect
Poynting vector (S)
pressure integral
primary mirror
point-spread function (PSF)
pulsar wind nebula (PWN)
quantum mechanics (QM)
quasar (QSO)
radiometer equation
radio telescope
RAPTOR
Rayleigh scattering
reddening
red noise
redshift-angular size relation
reflection nebula
reflector telescope
relativity
Rosetta
Rossiter-McLaughlin effect (RM effect)
ROTSE
Southern African Large Telescope (SALT)
Schmidt-Newton telescope
Schuster-Schwarzschild model
Sloan Digital Sky Survey (SDSS)
spectral energy distribution (SED)
Seyfert galaxy
SkyMapper
Sloan 2.5m Telescope
SN 1987A (1987A)
Snell's law
supernova remnant (SNR)
source function (S)
spacetime diagram
spectral power distribution (SPD)
speckle suppression
spectral line
spectrograph
spectrometer
spectroscope
spectroscopic binary
spectroscopy
speed of light (c)
Swope Supernova Survey (SSS)
stellar atmosphere
stellar distance determination
stellar structure
stray light
Strehl ratio
Strömgren photometric system
Subaru Telescope
superluminal motion
surface temperature
Swift
telescope
3C 273
3C 295
3C 48
Thirty Meter Telescope (TMT)
TRACE
transiting planet
terrestrial time (TT)
Two Micron All-sky Survey (2MASS)
two-stream approximation
Type Ia supernova
U
ultraviolet (UV)
UVOIR
V
variable star
Vega system
Virgo
vegetation red edge (VRE)
wavelength
wide binaries (WB)
William Herschel Telescope (WHT)
atmospheric window
WINGS
XBONG
XMM-Newton
Yolo telescope
zodiacal light

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