es of planets attached to them; and
though there are reasons for thinking that this is not the case with
all, it may be with some. Now if, after learning this, we look again at
the sky, we do so with very different eyes, for we realize that some of
these shining bodies are like ourselves in many things, and are shining
only with a light borrowed from the sun, while others are mighty glowing
suns themselves, shining by their own light, some greater and brighter,
some less than our sun. The next thing to do is to learn which are stars
and which are planets.
Of the planets you will soon learn to pick out one or two, and will
recognize them even if they do change their places--for instance, Venus
is at times very conspicuous, shining as an evening star in the west
soon after the sun goes down, or us a morning star before he gets up,
though you are not so likely to see her then; anyway, she is never found
very far from the sun. Jupiter is the only other planet that compares
with her in brilliancy, and he shines most beautifully. He is, of
course, much further away from us than Venus, but so much larger that he
rivals her in brightness. Saturn can be quite easily seen as a
conspicuous object, too, if you know where to look for him, and Mars is
sometimes very bright with a reddish glow. The others you would not be
able to distinguish.
It is to our earth's family of these eight large planets going steadily
round the same sun that we must give our attention first, before going
on to the distant stars. Many of the planets are accompanied by
satellites or moons, which circle round them. We may say that the sun is
our parent--father, mother, what you will--and that the planets are the
family of children, and that the moons are _their_ children. Our earth,
you see, has only one child, but that a very fine one, of which she may
well be proud.
When I say that the planets go round the sun in circles I am only
speaking generally; as a matter of fact, the orbits of the planets are
not perfect circles, though some are more circular than others. Instead
of this they are as a circle might look if it were pressed in from two
sides, and this is called an ellipse. The path of our own earth round
the sun is one of the most nearly circular of them all, and yet even in
her orbit she is a good deal nearer to the sun at one time than another.
Would you be surprised to hear that she is nearer in our winter and
further away in our summer? Yet t
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