Green-Mountain freeman. [volume] (Montpelier, Vt.) 1844-1884, 1877-10-31
The family Cirele.
Mars.

telescope with which he had discovered
the moons Of Jupiter, the crescent form Of
Venus, and many other wonders in the
heavens, he was altogether disappointed
His telescope was indeed too small TO show
any features of interest in Mars, though
the planet of war is much nearer to us
than Jupiter Mars is but small world
The diameter Of the planet is about 4,400
miles, that Of our earth being nearly 5000.
Jupiter, though much farther away has
his immense diameter of more than so 600
miles to make up, and much more than
make up, for the effect Of dsaI ce. With
his noble system of moons he appears II
remarkable object even with small teles
cope, but Mars shows fewer features Of
interest even with telescopes of considera-
BILE size.
1t was not, then, till very powerful tel
escapes had been constructed that astrono-
mers learned what we now know about
Mars.
1t is found that his surface is divided
into lanl and water, like the surface OF
are not nearly so large compared with his
continents and lands. You know that on
our own earth the water covers so much
larger surface than the land that the
great continents arc in reality islands
Europe, Asia and Africa together form one
great island; North and South America
another, not quite SO large; then CONF
Australia, Greenland, Madagascar, and SO
forth; all the lands being islands, larger
or smaller. On the other hand, except TIT
Caspian Sea and the Sea of Aral, there are
no large seas entirely landbound. In tho
case of Mars very different state o
things prevails, as you will see from the
three accompanying pictures (hithorto I'm
published), drawn by the famous EngisI
observer, Dawes (called the Eagle.eyed)
The third and best WAS drawn with teles
cope constructed by your famous optician
Alvan Clark, Of Cambridge, Mass. Th'
dark parts are the seas, the light parts be
ing land, or in some cases cloud OF snow
But in these pictures most of the lighEe
portions represent land; for they havt
been seen often so shaped, whereas clouds
of course, would change in shape.
The planet Mars, like our earth, turn
on its axis, so that it has day and night IL
we have. The length of its day is not yer,
different from that Of our own day. Gu
earth turns once on its axis ia -bu
before reading on, try to complete thi
sentence for yourself Every one know
that the earth's turning on its axis pro
duces day and night and nine persons on
of ten, if asked how long the earth take
in turning round her axis, will answer, 2
hours; and if asked how many times sh
turns on her axis in year, will say Sc
times, OF if disposed to be very exact
"about 3G5f times" But neither answe
is correct. The earth turns on her aXi
about 1861 times in each year, and eac
turning occupies % hours, sc minutes an
4 seconds and tenth of second. We
taking the ordinary day us the time c
a turning or rotation, lose count Of one re
tation each year. 1t is necessary to men
ton this, in order that when | tell you no,
long the day Of Mars is, you may be abb
correctly to compare it with our own day
Mars, then, turns on his axis in * hour,
81 minutes, % seconds and Z tenth part
of u second. So that Mars requires A
minutes, Is seconds and tenths of SEE
ond longer to turn his small body one
round than our earth requires to tm
round her much larger body. The con
, mon day of Mars is, however, only abo,
, 80 minutes longer than our common da,
Mars has IL long year, taking no les
+ than 687 of our days to complete his C
cult round the sun, 50 that his year las
only about one month and IL half less thu
two of ours.
, Like the earth, Mars has seasons, ft
: his polar axis, like that of the earth,
aslant, and at one part of his year bring
q his northern regions more fally mo SUI
light, at which time summer prevail
! there and winter in his southern region
! when at the opposite part of his year h
! southern regions are turned more full
sunward and have their summer, Viii
, winter prevails over his northern region
, Around his poles, us around the cal TIL
:. there are great masses of ice, insomut
> that it is very doubtful whether any inha
n itants of Mars have been able to p3netra
f to his poles, any more than Kane or Hay
!. or Mares or Parry, despite their coura.
- and endurance, have been able to real
= our northern pole, or Cook or Wilkes
~ James Ross, our antarctic pole.
In the summer of either hemisphere
- Mars, the north polar SHOWS becon
n greatly reduced in extent, us is natur;
" while 10 winter they reach to low latitude
+ showing that in parts of the planet CORE
y ponding to the United States, or mi
g Europe, as to latitude, bitter cold mi
% prevail for several weeks in succession
>, Prot. Il. 4. Proctor, IN 81. NjcE0IaS !
is NoCembcr.