There are a few things that never change


Table 1: Physical Constants (SI units)

constant symbol value units
Avogadro's number N 6.02E+23 mole-1
Boltzmann constant k 1.381E-23 J/K
Electric Charge e 1.602E-19 coulomb (C)
Gas Constant R 8.3145 J/K*mole
Gravitation G 6.672E-11 N*m2/kg2
Mass electron 9.11E-31 kg
Mass proton 1.67E-27 kg
Mass neutron 1.68E-27 kg
Mass alpha-particle 6.64E-27 kg
Plank's h 6.626E-34 J*s
Plank's hc 1.986E-25 J*m
Plank's hc/k 1.439E-02 m*°C
Radiation constant hc^2 5.955E-17 W*m2
Speed of light c 2.998E+08 m/s
Stefan-Boltzmann sigma 5.6705E-08 W/m2*K4

 

If there are others out there, this is how they'll find us


Table 2: Astronomical Constants (SI units)

constant body value units
Gravitational
Acceleration
Sea level 9.8067 m/s2
Luminosity Sun 3.826E+26 J/s
Mass Sun 1.989E+30 kg
Mass Earth 5.976E+24 kg
Atmospheric
Pressure
Sea level 1.013E+05 Pa
Radius Earth 6.371E+06 m
Radius Sun 6.970E+08 m
Earth's Orbital Velocity 2.978E+04 m/s