Examples from Nature: Planet Speeds
(Mean Miles Per Second/Hour)
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
29.76
21.78
18.52
15.00
8.12
6.00
4.23
3.37
2.95
107,136
78,408
66,672
54,000
29,232
21,600
15,228
12,132
10,620
Source: Rand McNally World Atlas (Chicago: 1965), page xxiii

Stellar Speeds
(Kilometers Per Second/Hour)
The Sun
Milky Way
Local Group
Virgo Supercluster
225
100
220
400
810,000
360,000
792,000
1,440,000
Source: Hartman, William K., and Chris Impev,
Astronomy: The Cosmic Journey, 5th ed
(Belmont, CA: Wadsworth Pub Co, 1994), p 665

Conversion to Miles Per Hour
The Sun
Milky Way
Local Group
Virgo Supercluster
503,010
223,560
305,428
894,240