With a magnifying power of 300 the
polar spots of Mars were distinctly visible and perfectly defined.
They were, I thought, less white than they appeared from the Earth,
but their colour was notably different from that of the planet's
general surface, differing almost as widely from the orange hue of
what I supposed to be land as from the greyish blue of the water. The
orange was, I thought, deeper than it appears through a telescope of
similar power on Earth. The seas were distinctly grey rather than
blue, especially when, by covering the greater part of the field, I
contrived for a moment to observe a sea alone, thus eliminating the
effect of contrast. The bands of Jupiter in their turn were more
notably distinct; their variety of colour as well as the contrast of
light and shade much more definite, and their irregularities more
unmistakable. A satellite was approaching the disc, and this afforded
me an opportunity of realising with especial clearness the difference
between observation through seventy or a hundred miles of terrestrial
atmosphere outside the object glass and observation in space.
Pages:
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86