| astronomical
unit |
AU |
1.49597870700E+13 |
cm |
1.49597870700E+11 |
m |
exact |
| atomic mass
unit, m(12C)/12 |
u |
1.66053906660E-24 |
gm |
1.66053906660E-27 |
kg |
5.00E-37 |
kg |
| Avogadro's
number |
NA |
|
6.02214076E+23 |
mole-1 |
|
|
| Boltzmann's constant |
k |
1.380649E-16 |
erg K-1 |
1.380649E-23 |
J K-1 |
exact |
| day |
day |
|
8.6400E+04 |
s |
|
exact |
| day, sidereal |
|
|
8.61640905E+04 |
s |
|
in 2009 |
| electron mass |
me |
9.1093837015E-28 |
gm |
9.1093837015E-31 |
kg |
2.80E-40 |
kg |
| elementary charge |
qe |
4.803204270E-10 |
esu |
1.602176634E-19 |
C |
exact |
| fine-structure constant |
α |
|
7.2973525693E-03 |
|
1.10E-12 |
|
1/α |
|
137.035999084 |
|
2.10E-08 |
| hydrogen atomic mass (in populations) |
mH |
|
1.007825 |
u |
|
|
|
| hydrogen molecular mass (in populations) |
mH2 |
|
2.015650 |
u |
|
|
| light year |
ly |
9.46052818E+17 |
cm |
9.46052818E+15 |
|
in 2000 |
| neutron mass |
mn |
1.67492749804E-24 |
gm |
1.67492749804E-27 |
kg |
9.50E-37 |
kg |
|
|
|
1.00866491595 |
u |
|
4.90E-10 |
u |
| Newton's constant of gravitation |
G |
6.67430E-08 |
cm3
gm-1 s-2 |
6.67430E-11 |
m3
kg-1 s-2 |
1.50E-15 |
m3
kg-1 s-2 |
| parsec |
pc |
1.37667319634E-02 |
cm |
1.37667319634E-05 |
m |
exact, truncated |
| Planck's constant |
h |
6.62607015E-27 |
erg s |
6.62607015E-34 |
J Hz-1 |
exact |
| |
ħ = h/2π |
1.05457182E-27 |
erg s |
1.05457182E-34 |
J Hz-1 |
exact, truncated |
| proton mass |
mp |
1.67262192369E-24 |
gm |
1.67262192369E-27 |
kg |
5.10E-37 |
kg |
|
|
|
1.007276466621 |
u |
|
5.30E-11 |
u |
| solar irradiance at Earth |
fÅ |
1.361E+06 |
erg s-1
cm-2 |
1361 |
W m-2 |
variable |
| solar luminosity |
Le |
3.828E+33 |
erg s-1 |
3.828E+26 |
W |
variable |
| solar mass |
Me |
1.98841E+33 |
gm |
1.98841E+30 |
kg |
7.00E+25 |
kg |
| solar mass parameter |
GMe |
1.327124421E+26 |
dyne cm2 |
1.327124421E+20 |
N m2 |
1.00E+12 |
N m2 |
| solar photospheric radius |
Re |
6.9566E+10 |
cm |
6.9566E+08 |
m |
1.40E+05 |
m |
| solar photospheric effective temperature |
Tee |
|
5771 |
K |
|
= (Le/4πσRe2)1/4 |
| speed of light in vacuum |
c |
2.99792458E+10 |
cm s-1 |
2.99792458E+08 |
m s-1 |
exact |
| standard acceleration of gravity |
g |
9.80665E+02 |
cm s-2 |
9.80665 |
m s-2 |
exact |
| standard atmospheric pressure |
atm |
1.01325E+06 |
dyne cm-2 |
1.01325E+05 |
N m-2 |
exact |
| Stefan-Boltzmann constant |
σ |
5.670374419E-05 |
erg s-1
cm-2 K-4 |
5.670374419E-08 |
W m-2
K-4 |
exact; truncated |
| vacuum electric permittivity |
ε0 |
--- |
|
8.8541878128E-12 |
farad m-1 |
1.30E-21 |
farad m-1 |
| vacuum magnetic permeability |
μ0 |
--- |
|
1.25663706212E-06 |
N amp-2 |
1.90E-16 |
N amp-2 |
| year, sidereal |
|
|
3.1558150E+07 |
s |
|
in 2000 |
| year, tropical |
yr |
|
3.1556925E+07 |
s |
|
in 2000 |
