How Big Is That 2

Physical and astronomical constants Gravitational constant

G = 6.67390 × 10-8 cm 3 gm -1sec-2 , ×10-11 m 3 kg -1 sec-2

Boltzmann constant

k = 1.380658 × 10 −16 erg K -1 , ×10 −23 joule K -1

Stefan-Boltzmann constant

σ = 5.67051 × 10 −5 erg sec -1 cm -2 K -4 , ×10 −8 joule sec -1 m -2 K -4

Planck constant

h = 6.6260755 × 10 −27 erg sec, × 10 −34 joule sec

Speed of light

c = 2.99792458 × 1010 cm sec -1 , ×108 m sec -1

Electron mass

me = 9.1093897 × 10−28 gm, × 10 −31 kg

Proton mass

mp = 1.6726231 × 10 −24 gm, × 10 −27 kg

Neutron mass

mn = 1.674929 × 10 −24 gm, × 10 −27 kg

Hydrogen mass

mH = 1.673534 × 10−24 gm, × 10−27 kg

Atomic mass unit

u = 1.6605402 × 10 −24 gm, × 10 −27 kg

Quantum of electric charge, cgs

e = 4.803206 × 10 −10 esu

Quantum of electric charge, SI

e = 1.60217733 × 10 −19 coul

Earth mass Earth radius Earth solar day Earth sidereal year

M⊕ = 5.97223 × 1027 gm, × 1024 kg R⊕ = 6.378 × 108 cm, × 106 m Day = 86400 sec P⊕ = yr = 3.155815 × 10 7 sec

Astronomical unit

AU = 1.4960 × 1013 cm, × 1011 m

Solar mass

M: = 1.98843 × 1033 gm, × 1030 kg

Solar radius

R: = 6.9599 × 1010 cm, × 108 m

Solar effective temperature

Te: = 5800 K

Solar luminosity

L: = 3.826 × 10 33 erg sec -1 , × 10 26 watt

Solar apparent bolometric magnitude Solar absolute bolometric magnitude Light year

mS = −26.82

Parsec

pc = 3.0857 × 1018 cm, × 1016 m = 3.2616 ly

Hubble constant

H 0 = 65 km sec-1 Mpc-1 = 20 km sec-1 Mly -1

MS = 4.75 ly = 9.4605 × 1017 cm, × 10 15 m

Color index, effective temperature and bolometric correction: B-V -0.35 -0.31 -0.3 -0.26 -0.24 -0.2 -0.16 -0.14 -0.12 -0.09 -0.06 0 0.03 0.06 0.09 0.15 0.2 0.33 0.38 0.45 0.47

Te 40000 31900 30000 24200 22100 18800 16400 15400 14500 13400 12400 10800 10200 9730 9260 8620 8190 7240 6930 6540 6450

BC -4.5 -3.34 -3.17 -2.5 -2.23 -1.77 -1.39 -1.21 -1.04 -0.85 -0.66 -0.4 -0.32 -0.25 -0.2 -0.15 -0.12 -0.08 -0.06 -0.04 -0.04

B-V 0.5 0.53 0.6 0.64 0.68 0.72 0.81 0.92 0.98 1.15 1.3 1.41 1.48 1.52 1.55 1.56 1.61 1.73 1.8 1.91

Te 6320 6200 5920 5780 5610 5490 5240 4780 4590 4410 4160 3920 3680 3500 3360 3230 3120 3050 2940 2640

BC -0.04 -0.05 -0.06 -0.07 -0.1 -0.15 -0.19 -0.25 -0.35 -0.65 -0.9 -1.2 -1.48 -1.76 -2.03 -2.31 -2.62 -3.21 -3.46 -4.1