Wien's Law for several wavelengths

Caveats and disclaimers: Technically, Wien's law applies to only thermally-emitted radiation (also referred to as a blackbody). Not every astrophysical process emits light like this - many other processes give rise to light emission, and those processes mean that the emitting matter is not necessarily (often not at all) at the temperatures suggested here. But this is a rule of thumb, and is good enough for wrapping your brain around the variety of kinds of light there are in the Universe.

Wien's law : temperature in K = 2.9x10^6 / wavelength in nm
Simple unit conversion yields: temperature in K = 2900 / wavelength in microns

wavelength temperature notes

2 nm 1.5 x 10^6 K = 1,500,000 K x-rays

200 nm 14,500 K ultraviolet

500 nm 5800 K visible

1600 nm 1800 K near-ir

100,000 nm 29 K far-ir

wavelength temperature notes

3.6 um 805 K IRAC band 1

4.5 um 644 K IRAC band 2

5.8 um 500 K IRAC band 3

8.0 um 363 K IRAC band 4

24 um 121 K MIPS band 1

70 um 41 K MIPS band 2

160 um 18 K MIPS band 3

wavelength	temperature	notes
2 nm	1.5 x 10^6 K = 1,500,000 K	x-rays
200 nm	14,500 K	ultraviolet
500 nm	5800 K	visible
1600 nm	1800 K	near-ir
100,000 nm	29 K	far-ir

wavelength	temperature	notes
3.6 um	805 K	IRAC band 1
4.5 um	644 K	IRAC band 2
5.8 um	500 K	IRAC band 3
8.0 um	363 K	IRAC band 4
24 um	121 K	MIPS band 1
70 um	41 K	MIPS band 2
160 um	18 K	MIPS band 3

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Last substantially modified 9 Feb 04 by rebull
Any opinions expressed here are well-reasoned and insightful, but in no way reflect those of NASA/JPL or Caltech. No electrons were harmed in the creation of these pages.

The research described here was partially carried out at IPAC, which is part of the Jet Propulsion Laboratory, operated by the California Institute of Technology, under a contract with the National Aeronautics and Space Administration.