Titania by John Simmons

Astronomical Data

This is a random list of planetary and Galactic data that I've needed from time to time, but had trouble finding on the Web.  The numbers are based on astronomy books I used in undergrad, and some of the values may have been updated since then, so take these numbers (especially Galactic data and data on Pluto/Charon) as close, but not necessarily exact.

Planets

Physical Data

Planet Mass

(1024 kg)

 Equatorial Radius

(km)

 Average Density

(103 kg m-3)

 Surface Gravity

(g)

 Escape Speed

(m s-1)

 Equilibrium Blackbody Temperature
(K)		 Observed Temperature

(K)
Mercury 0.33  2439 5.4 0.38 4.2 445 100-700
Venus 4.87 6052 5.2 0.91 10.3 325 700
Earth 5.97 6378 5.52 1.00 11.2 277 250-300
Mars 0.64 3393 3.9 0.39 5.1 225 210-300
Jupiter 1900 71398 1.40 2.74 61 122 110-150
Saturn 569 60000 6.9 1.17 36 90 95
Uranus 87 25559 1.19 0.94 21 63 58
Neptune 103 24800 1.66 1.15 24 50 56
Pluto 0.01 1140 0.5 0.03 2.1 44 40

Orbital Data

Planet Sydonic Period

(days)

 Sidereal Period

(days)

 Semimajor Axis

(106 km)

 Eccentricity Inclination to Ecliptic
(degrees)		 Sideral Rotation Period
Mercury 115.9 87.96 57.9 0.206 7.00 58.65 days
Venus 583.9 224.70 108.2 0.007 3.39 243 days
Earth -- 365.26 149.6 0.017 0.00 23h 56m 4.1s
Mars 779.9 686.98 228.0 0.093 1.85 24h 37m 22.6s
Jupiter 398.9 4333 778.3 0.048 1.31 9h 50.5m
Saturn 378.1 10759 1427 0.056 2.49 10h 14m
Uranus 369.7 30685 2871 0.047 0.77 17h 14m
Neptune 367.5 60188 4497 0.009 1.77 16h 3m
Pluto 366.7 90700 5913 0.249 17.15 6.439 days

Solar Data

Property Value
Mass 1.99 x 1030 kg
Radius 6.96 x 108 m
Mean density 1410 kg m-3
Surface gravity 2.74 x 102 m s-2
Escape speed 6.18 x 105 m s-1
Effective Temperature 5770 K
Luminosity 3.86 x 1026 W
Magnetic fields:
Sunspots 0.3 T
Global 0.0001 T
Network 0.002 T
Plages 0.02 T

Galactic Data

Property Approximate Value
Disk diameter 50 kpc
Halo diameter 100 kpc
Sun's distance from center 8.5 +/- 1.0 kpc
Height of Sun above disk 8 pc
Total mass 7.2 x 1011 solar masses
Mass of gas 8 x 109 solar masses
Mass of central bulge 4 x 1010 solar masses
Optical luminosity 3 x 1036 W
Density of stars in solar neighborhood 0.05 solar masses per parsec cubed



Last updated 30 April 2001