Ron Torell, former University of Nevada Extension livestock specialist now retired, wrote a few years back that most cows pay for themselves by age six. âThus, the longer a cow stays in the herd, the more profitable she becomes.
Naturally, these hours, minutes, and seconds are shorter than the solar hours, minutes, and seconds you are familiar with. One solar day is 24 solar hours long, and one sidereal day is 24 sidereal hours long, but one sidereal day is 23 solar hours and 56 solar minutes long. This exercise was based on a help section of CyberSky. A shareware version of CyberSky is available from http://www.cybersky.com .
Due to Mercury's 3:2 spinâorbit resonance, a solar day (the length between two meridian transits of the Sun) lasts about 176 Earth days. A sidereal day (the period of rotation) lasts about 58.7 Earth days.