REFERENCE DATA USED FOR COMPUTATIONS ON THIS WEB SITE
Values marked with ** are EXACT values and with * are adopted standards.
Speed of Light 299792458 m/s  ** (NIST)
299792.458 km/s
186282.397 mi/s
670616629.384 mi/h
1079252848.800 km/h
1 Foot (ft) 0.3048 m  **
1 Statute Mile (mi) 5280 ft  **
1760 yd
1609.344 m 
1.609344 km
0.8689762419006479 nmi
1 Kilometer (km) 1000 m  **
0.621371192237334 mi
3280.8398950131233596 ft
1093.6132983377077865 yd
1 Nautical Mile (nmi) 1852 m  **
1.852 km
1.1507794480235425 mi
2025.3718285214348206 yd
6076.1154855643044619 ft
1 Astronomical Unit  (AU) 149597870.700 km  * (IAU/NASA/JPL DE430)
92955807.273 mi
Light Time To Span 1 AU 499.004784 seconds
8 minutes and 19.004784 seconds
0.005775518331436996 day
Solar Radius 695508 km ±26 
432169 mi ±16
Earth Radius 6356.7519 km (Polar)      3949.9025 mi
6367.4443 km (Mean)       3956.5464 mi
6378.1366 km (Equatorial) 3963.1903 mi

flattening = f = 1/298.257 = 0.003352813178
(1 − f) = 0.996647186822
Lunar Radius 1736.0 km (Polar)         1078.70 mi
1737.05 km (Mean)         1079.35 mi
1738.1 km (Equatorial)    1080.00 mi
Geocentric Lunar Distance 363301 km (Min = Perigee)  225745 mi
384401 km (Mean)           238856 mi
405502 km (Max = Apogee)   251967 mi
Horizontal Parallax At 1 AU 8.79415"
0.0024428194444444°
Standard Julian Year 365.25 days  **
365 days and 6 hours
8766 hours
525960 minutes
31557600 seconds
Standard Gregorian Year 365.2425 days  **
365 days 5 hrs 49 min and 12 sec
8765.82 hours
525949.2 minutes
31556952 seconds
1 Light Year (LY) 9460730472580.8 km
5878625373183.6 mi
63241.0770880709446742 AU
0.3066013952202032 pc
1 Parsec (pc) 30856775670468 km
206264.80624709635488 AU
3.2615637619058885 LY
Standard Earth Gravity
9.80665 m/s2  *
1.000 G  *
32.17405 ft/s2
Newtonian Constant
Of Gravitation
0.0000000000667428 m3/kg/s2
Stefan-Boltzmann
Radiation Constant (σ)
0.000000056704 W/m2/s/T4
 
Physical Constants - NIST                 Planetary Fact Sheets - NASA
Jay Tanner - 2016