TABLE OF USEFUL ASTRONOMICAL FACTS.
Reading edition
The sun’s mean distance from the earth is 92,700,000 miles; his diameter is 865,000 miles, and he rotates in a period between 25 and 26 days.
The moon’s mean distance from the earth is 238,000 miles; the diameter of the moon is 2160 miles, and the time of revolution round the earth is 27.322 days.
THE PLANETS.
Mean Distance from the Sun in Millions of Miles. Periodic Time of Revolution in Days. Diameter of Planet in Miles. Axial Rotation.
Hrs. Mins. Secs.
Mercury 35.9 87.969 2,992 Uncertain.
Venus 67.0 224.70 7,660 Uncertain.
Earth 92.7 365.26 7,918 23 56 4.09
Mars 141 686.98 4,200 24 37 22.7
Jupiter 482 4,332.6 85,000 9 55 —
Saturn 884 10,759 71,000 10 14 23.8
Uranus 1,780 30,687 31,700 Unknown.
Neptune 2,780 60,127 34,500 Unknown.
THE SATELLITES OF MARS.
Name. Mean Distance from Centre of Mars. Periodic Time.
Hrs. Mins. Secs.
Phobos 5,800 miles. 7 39 14
Deimos 14,500 ” 30 17 54
THE SATELLITES OF JUPITER.
Name. Mean Distance from Centre of Jupiter. Periodic Time.
Days Hrs. Mins. Secs.
I 262,000 miles. 1 18 27 34
II 417,000 ” 3 13 13 42
III 664,000 ” 7 3 42 33
IV 1,170,000 ” 16 16 32 11
V 112,400 ” — 11 57 (?)
THE SATELLITES OF SATURN.
Name. Mean Distance from Centre of Saturn. Periodic Time.
Days Hrs. Mins. Secs.
Mimas 118,000 miles. 0 22 37 27.9
Enceladus 152,000 ” 1 8 53 6.7
Tethys 188,000 ” 1 21 18 25.7
Dione 241,000 ” 2 17 41 8.9
Rhea 337,000 ” 4 12 25 10.8
Titan 781,000 ” 15 22 41 25.2
Hyperion 946,000 ” 21 7 7 40.8
Iapetus 2,280,000 ” 79 7 54 40.4
A ninth satellite was discovered in August, 1898, by Prof. W. H. Pickering, but its mean distance and periodic time have not yet been determined with precision.
THE SATELLITES OF URANUS.
Name. Mean Distance from Centre of Uranus. Periodic Time. Days.
Ariel 119,000 miles. 2.520383
Umbriel 166,000 ” 4.144121
Titania 272,000 ” 8.705897
Oberon 363,000 ” 13.463269
THE SATELLITE OF NEPTUNE.
Name. Mean Distance from Centre of Neptune. Periodic Time. Days.
Anonymous 220,000 miles. 5.87690