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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, being 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 nearly the only 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 is. Challenges to visible-light viewing include light pollution, and weather, and high altitudes provide an advantage.


(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)
black-body radiation
BlackGEM
black hole (BH)
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
chirp mass (Mc)
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
cyclotron radiation
Discovery Channel Telescope (DCT)
Dark Energy Survey (DES)
diffraction
Doppler shift
Dragone telescope
earthshine
extragalactic background light (EBL)
exoplanet eclipse light curve
eclipsing binary
European Extremely Large Telescope (E-ELT)
effective radius (Re)
electromagnetic spectrum
elevation range
electromagnetism (EM)
emission
electromagnetic radiation (EMR)
epoch of reionization (EOR)
escape velocity (Ve)
European Southern Observatory Very Large Telescope (ESO VLT)
Euclid
extreme ultraviolet (EUV)
extreme adaptive optics (ExAO)
extinction
Faraday rotation
far infrared (FIR)
filter
focal length
focal plane array (FPA)
Fabry-Pérot interferometer (FPI)
Gaia
G band
G-CLEF
Gemini Observatory
geodesic
Giant Magellan Telescope (GMT)
Gould's Belt Distances Survey (GOBELINS)
general relativity (GR)
GRANAT
grating
gravitational lensing
gravity
greenhouse effect
Gran Telescopio Canarias (GTC)
gravitational wave spectrum
gravitational wave strain (h)
H-alpha (Ha)
Hawaii K-band Galaxy Survey
Hewitt & Burbidge Catalog (HB87)
HCI
HERMES
Holmberg radius
Hubble Space Telescope (HST)
I band
IceCube
infrared (IR)
INTEGRAL
interference
interferometer
interferometry
IOTA
IRTF
JUICE
Juno
K band
Kramers opacity law
Large Binocular Telescope (LBT)
Las Cumbres Observatory (LCO)
light pollution
Lorentz transformation
LUVOIR
Lyot stop
Magellan Telescopes
magnitude
mass spectrometer
Maxwell's equations
MeerLICHT
multi-messenger astronomy
near infrared (NIR)
nitrogen (N)
New Technology Telescope (NTT)
observatory
OGLE
OIR
1 Jansky Empty Field Survey (1 Jy)
optical double
optical interferometer
optics
PanCET
panchromatic
photochemistry
Pi of the Sky
radiometer equation
radio telescope
RAPTOR
red noise
reflector telescope
Rosetta
ROTSE
Southern African Large Telescope (SALT)
Sloan Digital Sky Survey (SDSS)
spectral energy distribution (SED)
SkyMapper
Sloan 2.5m Telescope
source function (S)
spectrograph
spectrometer
spectroscope
spectroscopy
Swope Supernova Survey (SSS)
stellar distance determination
Strömgren photometric system
Subaru Telescope
Swift
telescope
3C 273
3C 295
3C 48
Thirty Meter Telescope (TMT)
TRACE
U
ultraviolet (UV)
UVOIR
V
Vega system
Virgo
vegetation red edge (VRE)
wavelength
William Herschel Telescope (WHT)
atmospheric window
WINGS
XBONG
XMM-Newton
zodiacal light

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