| Olinthus Gilbert Gregory - 1802 - 590 pages
...days and apparent Time. 73 by 24 hours, will give 23*" 56™ 4* for the length Sofa sidereal day. 115. **The mean and apparent solar days are never equal, except when the sun's daily motion in** rightascension is 59' 8"; this is nearly the case about April ifth, June i5th, September ist, and December... | |
| Edward T W. Polehampton - 1815 - 568 pages
...will be 23h 56' 4",iy The astronomical, or civil, day is constantly changing. This variation arises **from two causes; 1. The unequal motion of the earth...when the sun's daily motion in right ascension is** 5g' 8". This is the case about April Hit It, June l6th, September 1st, and December 25th ; on these... | |
| James Smith - 1815 - 684 pages
...The length both of the astronomical and the civil day is constantly chiinging. This variation arises **from two causes: 1. The unequal motion of the earth in its orbit. 2. The** nMiquity of that orbit to the plane of the- equator. The mean and apparent solar days are never equal,... | |
| Alexander Jamieson - 1821 - 448 pages
...cannot exceed 2° 42'. The astronomical, or civil, day is constantly changing. This variation arises **from two causes; 1. The unequal motion of the earth...obliquity of that orbit to the plane of the equator. The** annual intersection of the equator with the ecliptic is not always in the same point: but is retrograde,... | |
| 1823 - 894 pages
...at the same moment. True time is obtained by adding or subtracting this equation to the mean time. **The mean and apparent solar days are never equal,...when the sun's daily motion in right ascension is** 59' 8" ; this is nearly the case about April I5th, June 151)1, September ist, and December 24th : on... | |
| James Mitchell - 1823 - 666 pages
...day will be 23* 5G'4»-l. The astronomical or civil day is constantly changing. This variation arises **from two causes : 1. The unequal motion of the earth in its** 01 bit ; 2. The obliquity of that orbit to the plane of the equator. The mean and apparent solar days... | |
| Perry Fairfax Nursey - 1828 - 410 pages
...perturbations produced by the latter causes will make but little or no variation in the Examples already given. **The mean and apparent solar days are never equal,...when the sun's daily motion in right ascension is** 59 minutes 8 seconds; -which obtains about the 15th of April, 15th of June, 1st of September, and 24th... | |
| Thomas Kerigan - 1838 - 804 pages
...length. But, owing to the inequalities of the earth's annual motion in an elliptic orbit, combined with **the obliquity of that orbit to the plane of the equator, the** length of the solar day is constantly varying. And because the ecliptic is inclined to the equator... | |
| Popular encyclopedia - 1846 - 886 pages
...woulc change a degree every day, ami then the siderea days would be 4 minutes shorter than the solar. **The mean and apparent solar days are never equal,...when the sun's daily motion in right ascension is** 59' ; which is nearly the case about the 15th of April, the 15th of June, the 1st of September, and... | |
| Mary Somerville - 1846 - 506 pages
...amounting to as much as sixteen minutes. The apparent and mean time coincide four times in the year ; **when the sun's daily motion in right ascension is equal to 59' 8"-33** in a mean solar day, which happens about the 1 6th of April, the 16th of June, the 1st of September,... | |
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