"Yes, and when we get to Mars there'll be plenty to look at,"
suggested Jack. "We can see the rings around it."
"Mars hasn't any rings around it," retorted Mark, who had a good
memory for scientific facts. "That's Saturn you're thinking of."
"Oh, yes, so it is. But hasn't Mars got a lot of moons, or
something like that? Seems to me I've heard about 'em."
"Mars has two moons, or satellites," stated Mr. Roumann, who had
studied much about the red planet, "but they do not amount to
much, compared to our moon. One is about ten thousand miles from
Mars, and is called Deimos, and the other, which is but sixteen
hundred miles from the planet, is called Phobos by astronomers."
"And how far away is our moon from the earth?" asked Mark.
"It varies from about two hundred and fifty-two thousand miles to
two hundred and twenty-one thousand miles."
"Then I should think the people on Mars would get more light from
their two moons, so much closer to them, than we do from our
moon, so far off," remarked Jack.
"No, they don't, at least as far as we know. The one closest to
them gives about one-sixtieth of our moonlight, and the outer one
about one twelve-hundredth, so you see that's not much.
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