e Heavens three times a day. The second
gravitates at 20,000 kilometers (12,400 miles), and turns round its
center of attraction in thirty hours and eighteen minutes. These two
satellites were discovered by Mr. Hall, at the University of Washington,
in the month of August, 1877.

* * * * *

Among the finest and most interesting of the celestial phenomena admired
by the Martians, at certain epochs of the year,--now at night when the
Sun has plunged into his fiery bed, now in the morning, a little before
the aurora,--is a magnificent star of first magnitude, never far removed
from the orb of day, which presents to them the same aspects as does
Venus to ourselves. This splendid orb, which has doubtless received the
most flattering names from those who contemplate it, this radiant star
of a beautiful greenish blue, courses in space accompanied by a little
satellite, sparkling like some splendid diamond, after sunset, in the
clear sky of Mars. This superb orb is the Earth, and the little star
accompanying it is the Moon.

[Illustration: FIG. 44.--The Earth viewed from Mars.]

Yes, to the Martians our Earth is a star of the morning and evening;
doubtless they have determined her phases. Many a vow, and many a hope
must have been wafted toward her, more than one broken heart must have
permitted its unrealized dreams to wander forth to our planet as to an
abode of happiness where all who have suffered in their native world
might find a haven. But our planet, alas! is not as perfect as they
imagine.

We must not dally upon Mars, but hasten our celestial excursion toward
Jupiter.

CHAPTER VI

THE PLANETS

_B._--JUPITER, SATURN, URANUS, NEPTUNE.

Before we attack the giant world of our system, we must halt for a few
moments upon the minor planets which circulate between the orbit of Mars
and that of Jupiter. These minute asters, little worlds, the largest of
which measures scarcely more than 100 kilometers (62 miles) in diameter,
are fragments of cosmic matter that once belonged to a vast ring, formed
at the time when the solar system was only an immense nebula; and which,
instead of condensing into a single globe coursing between Mars and
Jupiter, split up into a considerable quantity of particles constituting
at the present time the curious and highly interesting Republic of the
Asteroids.

These lilliputian worlds at first received the names of the more
celebrated of the mino