The Golden Age of Science Fiction Volume IX (Arthur Leo Zagat) читать бесплатно онлайн полную версию книги (ч. notes)

FOOTNOTES

1

The exact diameters of the planets are difficult to measure owing to irradiation, and estimates of various authorities differ, especially with regard to the more distant planets.

2

The “terminator” is the boundary between the lighted and the dark portion of the disc.

3

Those who have seen the undercliff in the Isle of Wight will be able to form some idea of the terraces of the lunar ring-mountains, as they are very similar formations.

4

It is not yet ascertained with certainty whether Mercury and Venus rotate in about twenty-four hours, or whether the period is the same as that of their revolution round the sun. The evidence seems to point to the latter period.

5

Most probably the larger planets possess satellites which have yet to be discovered.

6

This is the case as regards separate satellites; but it may be pointed out that a similar thing must occur in regard to the rings of Saturn. The rings are composed of swarms of satellites so small that they can only be termed particles, and these particles at the inner edge of the “crape ring” revolve round Saturn in 5 hours and 33 minutes, the inner edge of the ring being only about 47,000 miles from the centre of the planet. The planet itself revolves on its axis in 10-1/4 hours. Thus, an immense number of these minute satellites must revolve round the planet in less time than it takes the planet to make one rotation. It is calculated that the particles in the outer edge of the next ring complete one revolution round the planet in 14 hours and 28 seconds.