| Mass of Sun = 1.989 x 1030 kg |
| Radius of Sun = 6.9599 x 108 m ~ 7.0 x 105 km |
| Luminosity of Sun = 3.827 x 1026 J/s |
| Mass of Earth = 5.976 x 1024 kg |
| Radius of Earth (equator) = 6378.164 km |
| Mass of the Moon = 7.350 x 1022 kg |
| Radius of Moon = 1738 km |
| Radius of Moon's Orbit = 3.844 x 108 m ~ 384,000 km |
| Mass of proton = mp = 1.672 x 10-27 kg |
| Mass of electron = me = 9.109 x 10-31 kg |
| Speed of Light = c = 2.997925 x 108 m/s |
| Gravitational Constant = G = 6.673 x 10-11 Nm2/kg2 |
| Planck's Constant = h = 6.626 x 10-34 J s = 4.136 x 10-15 eV s |
| Boltzmann's Constant = k = 1.381 x 10-23 J/K = 8.617 x 10-5 eV/K |
| Astronomical Unit (AU) = 1.495979 x 1011 m ~ 150,000,000 km |
| Light Year (ly) = 9.46053 x 1015 m = 9.46053 x 1012 km = 63,240 AU |
| Parsec (pc) = 3.261633 ly = 206,265 AU = 3.085678 x 1016 m |
| 1 kiloparsec (kpc) = 103 pc 1 Megaparsec (Mpc) = 106 pc |
| Day (d) = 8.640 x 104 s |
| Tropical Year = 365.241219878 d |
| Sidereal Year = 365.256366 d ~ 3.156 x 107 s |
| Celsius to Kelvin Temperature: K = oC + 273 |
| Farenheit to Celsius Temperature: oC = 5(oF - 32) / 9 |
| 1 Inch = 2.54 cm |
| 1 Angstrom (Å) = 10-10 m |
| 1 Watt (W) = 1 J/s |
| 1 Joule (J) = 107 ergs |
| 1 eV = 1.602 x 10-19 J |
| 1 Megaton = 4 x 1015 J |
| 1 radian (rad) = 57.30o 1o = 0.01745 rad circle = 360o = 2π rad |
| 1 arc min = 1/60 degree = 2.909 x 10-4 rad |
| 1 arc sec = 1/3600 degree = 4.848 x 10-6 rad |