Astrophysics (Index)About

near infrared

(NIR, near-IR)
(electromagnetic radiation in the range of 800-2500 nm)

Near infrared (NIR or near-IR) is infrared radiation adjacent to visible light within the electromagnetic radiation spectrum, with wavelengths 750-2500 nm (all infrared's range being 750 nm to 1 mm, slightly different ranges are also cited for these). The essential difference between NIR and visible light is that NIR's wavelength is just outside the range that the human eye is sensitive to and the optical equipment for NIR is largely the same as that for visible light and modern research optical telescopes typically can observe at some or all NIR wavelengths as well. Sources producing visible light generally produce some NIR, and some sources are at distances such that redshift moves their visible light into the NIR band. Among the uses for NIR astronomy is the study of cool stars. Also, of use is that NIR is less affected by dust than visible light: objects hidden in dusty nebulae might be observed in infrared. A disadvantage of NIR observation is that some of its wavelengths are blocked by the atmosphere, and ground observation is confined to a few spectral bands within which the atmosphere is transparent to NIR (atmospheric windows). Observation from a high altitude reduces this issue.


(infrared,EMR,spectrum,band)
Further reading:
https://en.wikipedia.org/wiki/Near_infrared
https://en.wikipedia.org/wiki/Infrared_astronomy
http://www.icc.dur.ac.uk/~tt/Lectures/Galaxies/Images/Infrared/Regions/irregions.html
WaveLFreqPhoton
Energy
  
750nm400THz1.7eVbeginnear infrared
2500nm120THz496meVendnear infrared

Referenced by pages:
angstrom (Å)
Boötes Field
Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS)
Canada-France-Hawaii Telescope (CFHT)
CorMASS
Lowell Discovery Telescope (LDT)
DENIS
Dark Energy Survey (DES)
ESO 3.6m Telescope
European Southern Observatory Very Large Telescope (ESO VLT)
Euclid
first galaxies
Gaia
GaiaNIR
Galileo
Gemini Observatory
Giant Magellan Telescope (GMT)
Gemini Planet Imager (GPI)
griz photometric system
Gran Telescopio Canarias (GTC)
HARMONI
Hawaii K-band Galaxy Survey
High Definition Space Telescope (HDST)
helium 1083 nm line
NEWS
Hubble Space Telescope (HST)
I band
infrared (IR)
JHK photometric system (JHK)
K band
K-type star (K)
Keck Observatory
kilonova (KN)
KMOS
KMOS3D
L-type star (L)
LUVOIR
Magellan Telescopes
M-type star (M)
MICADO
Mimir
MKO photometric system
MMT
MMX
Multi-object Optical and Near-IR Spectrograph (MOONS)
Multiwavelength Survey by Yale-Chile (MUSYC)
NEAR Shoemaker (NEAR)
NIRPS
New Technology Telescope (NTT)
optics
PanCET
passband
Palomar Testbed Interferometer (PTI)
reflector telescope
radial velocity method
Sloan Digital Sky Survey (SDSS)
spectral energy distribution (SED)
SIMP
SINS
SOAR
SOFIA
SPECULOOS
SPHEREx
SPIRou
Subaru Telescope
Subaru PFS
University of Tokyo Atacama Observatory (TAO)
3D-HST
Telescopio Nazionale Galileo (TNG)
tip of the red-giant branch (TRGB)
TripleSpec (TSpec)
Two Micron All-sky Survey (2MASS)
ugriz photometric system
UltraVISTA
James Webb Space Telescope (JWST)
Roman Space Telescope (RST)
William Herschel Telescope (WHT)
atmospheric window
WINGS
FourStar Galaxy Evolution Survey (ZFOURGE)

Index