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night. It has not yet been decided whether this was a satellite, because Saturn has been among the countless faint stars of the Milky Way, among which the satellite might be lost.
The following is a list of the eight satellites, with their distances from the planet in radii of the latter, their times of revolution, and the discoverer of each:
| No. | Name. | Discoverer. | Date of Discovery. | Distance from Planet. | Time of Revolution. |
|---|---|---|---|---|---|
| 70d. 23h. | |||||
| 1 | Mimas | Herschel | 1789 | 3.3 | 700 2323 |
| 2 | Enceledas | Herschel | 1789 | 4.3 | 701 239 |
| 3 | Tethys | Cassini | 1684 | 5.3 | 701 2321 |
| 4 | Dione | Cassini | 1684 | 6.8 | 702 2318 |
| 5 | Rhea | Cassini | 1672 | 9.5 | 704 2312 |
| 6 | Titan | Huyghens | 1655 | 21.7 | 7015 2323 |
| 7 | Hyperion | Bond | 1848 | 26.8 | 7021 237 |
| 8 | Japetus | Cassini | 1671 | 64.4 | 7070 2322 |
The most noteworthy features of this list are the wide range of distances among the satellites, and the relation between the times of revolution of the four inner ones. The five inner ones seem to form a group by themselves. Then there is a gap exceeding in breadth the distance of the innermost of the five, when we have another group of two, Titan and Hyperion. Then there is a gap wider than the distance of Hyperion, outside of which comes Japetus, the outermost yet known.
A curious relation among the periods is that the period of the third satellite is almost exactly twice that of the first; and that of the fourth almost twice that of the