The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1903-10-18
BY Prof. o. T. Denny.


Our attention was last occupied with
the consideration of the planet Saturn.
About 60 degrees west of Saturn and
nearly the same distance from the
western horizon is the fiery planet Mars.
Because of it's reddish hue and its blaz-
ing appearance il was deemed fitting to
name it in honor of the god of war.
II has always been fancy of poetic or
imaginative people to invest the heaV-
emily bodies with human or divine at
tributes, and in some cases, at least,
the suggestion is very pleasing. Thus,
the sacred writer says, "Canst thou
bind the sweet influence of the Pleiades,
or loose the bonds of Orion?' And one
of our modern poets speaks of
''The glow of Venus and the glare of
The tranquil beauty of the lesser stars"
But though Mars has long been as
sociated, in the imagination, with the
bloody scenes of war, he is really
very peaceable and quiet member of
the solar family, shining usually about
as brightly as star of the first magni-
tude, but under more favorable circum-
stances. fairly rivaling the brilliance
of old Jupiter himself Just now it is
TOO far away and too near the glow
of the evening sky to attract much at
tention, and the careless observer may
fail to detect it.. The moon passed it
on Sept. % and will do so again on Oct.
"a and on Nov. %. But each month
will carry it farther and farther in the
direction of the sun, whose superior
rays will render it inconspicuous for a
time. and we shall then have to defer
further observation till more con-
Tenient season"
simple diagram will show the rela-
tive positions of Mars and the earth
in their orbits round the sun. All the
planets, including the earth, reVolve
around the sun in orbits that are nearly
circular. or, more exactly, somewhat
elliptical. AS the orbit of Mars COM
pletely enVelopS that of the earth, it
must always be at greater distance
from the sun than the earth is. The
earths average distance is nearly 3d.
100000 miles, while that of Mars is
14l,O0O,000. When the earth is between
the sun and Mars, so that Mars is OPP
posite the sun, Mars is said to be in
opposition, and its distance from the
earth is then equal to the difference of
their distances from the sun, or 141,-
100000 minus 93000,00 equals AS 900, =
600. When the sun is between the two
bodies so that the sun and planet are
seen together, or in the same direction,
the planet is said to be in conjunction;
and the distance from the earth is then
equal to the sum of their distances, or
to $4,000, 900 plus 93,000,000 equals
2S4,OO0,OO0. Thus it appears that Mars
is, on an average, about five times as
far from US at conjunction, and there
fore becoming more and more unfavor-
able for observation. The last opposi-
ton was March %, and since that time
till recently Mars has been somewhat
favOrably situated for study.
Now the distances given above are
only average distances, or what they
But since Their are ellipses, these dis
tances will vary considerably. Thus,
If Mars is at c in the figure and earth
at f., the distance may be 24S, 100000
miles; while if Mars is at M and earth
at +, the distance is only about 35,000,-
000 This is the famous opposition
which Mars reaches only at long peri
DDS of fifteen to seventeen years, and
then the conditions are so favorable
that remarkable distances have been
made. Thus, in 1852 snowcaps were
seen around the poles, in 1877 Hall dis
covered that Mars has two moons
which was before unknown, and in
1892, fifteen years later, also in 1894
other remarkable discoveries were
made, some of which are noted below
We can also see that since Mars is
about seven times as near the earth
at favorable opposition as at an un-
favorable conjunction, the apparent
diameter of Mars will be seven times
as large in the former case as in the
latter; and as the disc, or face, of the
body varies as the square of the dame
ter, 1t will look about fifty times as
large, as shown in the diagram.
We are now prepared to discuss
some of the wonderful phenomena OBJ
served on Mars by the aid of large
teIescopes,W Mars is at one of these
favorable oppositions. After noting
briefly the fact that in some parts of
the surface it presents the appearance
of a reddish ochre, which was sup
posed to be land, and in others a green
lsh tinge which was called water, and
the further fact that the supposed