## Astronomical Constants and Tables

The following is a compilation of various useful astronomical constants and solar system statistics. We cannot guarantee their accuracy.

#### Numerical and Physical Constants

Value Symbol Explanation
71°39'49.1"W   Frosty Drew Observatory Longitude
41°22'01.5"N   Frosty Drew Observatory Latitude
4.88 meters   Frosty Drew Observatory Altitude
3.141592654 π Ratio of circumference to diameter of a circle
0.017453293 π/180° Degree in radian measure
57.29577951 180°/π Radian in degree measure
1.609344   Mile in kilometers *
0.621371192   Kilometer in miles
299792458 m/s c Speed of light in a vacuum *
0.01720209895 k Gaussian gravitational constant
66.72×10-12m3/(kg×s2) G Constant of Gravitation
149597870.691 km AU Astronomical Unit
2451544.5 J2000 Julian date for midnight January 1, 2000 *
10.0×10-9 m Å Angstrom *
206264.8062 AU pc Parsec (1 pc = 3.269866 ly = 30.93532×1012 km)
63080.5 AU ly Light Year (1 ly = 9.460730×1012 km)
9192631770 # s Standard second *
60 s m Standard minute *
3600 s h Standard hour *
86400 s d Standard day *
36525 d C Julian century *
365.25 d y Julian year *
365.242191   Tropical year (equinoxes)
365.256363   Sidereal year (360°)
365.259635   Anomalistic year (nodes)
346.620072   Eclipse year
23h 56m 04s.1   Sidereal day
0.99726968   Sidereal day in solar units
1.0027377795   Solar day in sidereal day units
29.530588   Lunar synodic month
27.321660   Lunar siderial month
5029.0966   General precession (arc seconds per century)
* Value is exact by definition

# In 1967 the second was defined as: "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of ground state of the cesium 133 atom." Effectively, this says the second is exactly what the atomic clock in the National Institute of Standards and Technology says is a second.

#### Solar Data

Value Explanation
5800°K Temperature of Photosphere
5.0 Absolute Magnitude
-26.8 Apparent Magnitude
1.989x1030Mass [kilograms]
3.83x1026 Luminosity [watts]
1.37x103 Constant [watts/m2] at 1 AU
G2V Spectra classification
1392000 km Diameter
25.66 d Period

This document was authored by Les Coleman and is subject to Copyrights belonging to Les Coleman. This material may be referenced and reproduced as long as proper attribution is given as specified in Proper Usage Guidelines for Frosty Drew and Related Materials.