Understanding Spectra from the Earth
Supplement 2.5: Radiometric Quantities
The specific emittance
M
M
f
=
2
π
f
2
c
2
h
f
exp
{
h
f
/
k
T
}
−
1
M
λ
=
2
π
h
c
2
λ
5
1
exp
{
h
c
/
λ
k
T
}
−
1
The radiance
L
L
f
=
2
f
2
c
2
h
f
exp
{
h
f
/
k
T
}
−
1
L
λ
=
2
h
c
2
λ
5
1
exp
{
h
c
/
λ
k
T
}
−
1
