411 REFERENCE · Wikibooks
Pulsars and neutron stars/Useful parameters and constants
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Speed of light: 299 792 458m/s
1 parsec = 3.0857 x 1016m = 3.26156 ly
1 G = 10-4 T
The solar system
1 astronomical unit AU: 1.4960 x 1011m
Planet Mass (solar mass) Orbital period (yr) Semi-major axis (AU) Mercury 0.24 0.39 Venus 0.62 0.72 Earth 1.00 1.00 Mars 1.88 1.52 Jupiter 11.86 5.20 Saturn 29.46 9.54 Uranus 84.01 19.22 Neptune 164.8 30.06
Time and dates
Modified Julian Date
Date MJD 17th Nov 1858 0 1 Jan 1968 39856 1 Jan 1980 44239 1 Jan 1990 47892 1 Jan 1995 49718 1 Jan 2000 51544 1 Jan 2005 53371 1 Jan 2010 55197 1 Jan 2015 57023 1 Jan 2016 57388