THE SUN AND PLANETS.
| Name. | Sidereal period. | Mean distance from Sun. Millions of miles. | Diameter. Miles. | Surface. Earth=1. | Volume. Earth=1. | Mass. Earth=1. | Density. Earth=1. | Axial Rotation. d. h. m. | Force of gravity. Fall: Ft. in 1 sec. | Velocity in orbit. Miles per hour | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| SUN | ..... | ..... | 866,200 | 11,946 | 1,305,000 | 332,000 | 0.25 | 25 7 48 | 461 | ||
| h. m. s. | |||||||||||
| MERCURY | 88 days. | 36 | 3,008 | 0.144 | 0.055 | 0.066 | 1.26 | 24 5 30 | 7 | 107,000 | |
| VENUS | 225 ″ | 67 | 7,480 | 0.891 | 0.841 | 0.782 | 0.92 | 23 21 23 | 14 | 78,000 | |
| EARTH | 365 ″ | 93 | 7,926 | 1.000 | 1.000 | 1.000 | 1.00 | 23 56 4 | 16 | 66,000 | |
| MARS | 687 ″ | 141 | 5,000 | 0.398 | 0.251 | 0.107 | 0.45 | 24 37 23 | 4 | 53,000 | |
| Minor Planets | |||||||||||
| Eros (433) | 1.76 years. | ..... | 18 | Eros is the nearest to the Sun of the Minor Planets, part of its orbit falling between the Earth and Mars. | |||||||
| Vesta (4) | 3.6 ″ | 219 | 214 | Vesta is the largest of the Minor Planets. | |||||||
| Thule (279) | 8.8 ″ | 396 | ..... | Thule is the most distant from the Sun of the Minor Planets. | |||||||
| JUPITER | 11.8 ″ | 483 | 88,439 | 124 | 1,389 | 317 | 0.23 | 9 55 21 | 41 | 29,000 | |
| SATURN | 29.4 ″ | 886 | 75,036 | 89 | 848 | 94 | 0.11 | 10 29 17 | 18 | 21,000 | |
| URANUS | 84.0 ″ | 1782 | 30,875 | 15 | 59 | 14 | 0.25 | ? | 13 | 15,000 | |
| NEPTUNE | 164.6 ″ | 2792 | 37,205 | 21 | 103 | 17 | 0.17 | ? | 12 | 12,000 | |
SATELLITE OF THE EARTH.
| Name. | Sidereal period. d. h. m. | Distance from Earth. Miles. | Diameter Miles. | Surface. Earth=1. | Volume. Earth=1. | Mass. Earth=1. | Density. Earth=1. | Axial Rotation. d. h. m. | Force of gravity. Fall: Feet in 1 sec. | Velocity in orbit. Miles per hour. | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| MOON | 27 7 43 | 237,300 | 2,160 | 0.074 | 0.02034 | 0.0128 | 0.63 | 27 7 43 | 2.48 | 2,273 |
SATELLITES OF MARS.
| Name. | Discoverer. | Mean distance from Mars. Miles. | Sidereal period. d. h. m. | Diameter. Miles. | Maximum elongation. ″ | Apparent star magnitude. | |
|---|---|---|---|---|---|---|---|
| 1. PHOBOS | A. Hall, August 17, 1877. | 6,000 | 0 7 39 | 7 | 12 | 11½ | |
| 2. DEIMOS | A. Hall, August 11, 1877. | 15,000 | 1 6 18 | 6 | 32 | 13½ |
SATELLITES OF JUPITER.
| Name. | Discoverer. | Mean distance from Jupiter. Miles. | Sidereal period. d. h. m. | Diameter. Miles. | Apparent diameter of Jupiter seen from satellite. ° ″ | Apparent star magnitude. | ||
|---|---|---|---|---|---|---|---|---|
| 5. | Barnard | ....... | 0 11 49 | ? | ..... | .... | ||
| 1. IO | ............... | 267,000 | 1 18 29 | 2,390 | 19 49 | 7 | ||
| 2. EUROPA | Galileo, January 7-13, 1610. | 425,000 | 3 13 13 | 2,120 | 12 25 | 7 | ||
| 3. GANYMEDE | ............... | 678,000 | 7 4 0 | 3,980 | 7 47 | 6 | ||
| 4. CALLISTO | ............... | 1,192,000 | 16 18 5 | 2,970 | 4 25 | 7 |
SATELLITES OF SATURN.
| Name. | Discoverer. | Mean distance from Saturn. Miles. | Sidereal period. d. h. m. | Diameter. Miles. | Apparent diameter of Saturn seen from satellite. ° | Apparent star magnitude. | |
|---|---|---|---|---|---|---|---|
| 1. MIMAS | Sir W. Herschel, Sept, 17, 1789 | 115,000 | 0 22 37 | 1,000 | 33 | 17 | |
| 2. ENCELADUS | ″ ″ Aug. 28, 1789 | 147,000 | 1 8 53 | ? | 26 | 15 | |
| 3. TETHYS | J. D. Cassini, March, 1684 | 183,000 | 1 21 18 | 500 | 21 | 13 | |
| 4. DIONE | ″ ″ March, 1684 | 234,000 | 2 17 41 | 500 | 16 | 12 | |
| 5. RHEA | ″ ″ Dec. 23, 1672 | 327,000 | 4 12 25 | 1,200 | 12 | 10 | |
| 6. TITAN | Huygens, Mar. 25, 1653 | 758,000 | 15 22 41 | 3,300 | 5 | 8 | |
| 7. HYPERION | W. Bond & Lassell, Sept, 19, 1848 | 916,000 | 21 7 7 | ? | 4 | 17 | |
| 8. IAPETUS | J. D. Cassini, Oct. 25, 1671 | 2,221,000 | 79 7 53 | 1,800 | 2 | 9 |