Taking the earth’s diameter at 7912 miles, the moon’s diameter, 2163 miles, and the height of Mount Everest as 29,000 feet, I find that
| Everest | = | 1 | , and | Dörfel | = | 1 |
| Earth’s diameter | 1440 | moon’s diameter | 492 |
From which it follows that the lunar mountains are proportionately about three times higher than those on the earth.
According to an hypothesis recently advanced by Dr. See, all the satellites of the solar system, including our moon, were “captured” by their primaries. He thinks, therefore, that the “moon came to earth from heavenly space.”[97]
CHAPTER VI
Mars
Mars was called by the ancients “the vanishing star,” owing to the long periods during which it is practically invisible from the earth.[98] It was also called πυρόεις and Hercules.
I have seen it stated in a book on the “Solar System” by a well-known astronomer that the axis of Mars “is inclined to the plane of the orbit” at an angle of 24° 50′! But this is quite erroneous. The angle given is the angle between the plane of the planet’s equator and the plane of its orbit, which is quite a different thing. This angle, which may be called the obliquity of Mars’ ecliptic, does not differ much from that of the earth. Lowell finds it 23° 13′ from observations in 1907.[99]