The Vermont watchman. [volume] (Montpelier, Vt.) 1883-1911, 1899-01-04
An Eclipse of the Moon--. Eclipses in
General.

On Decemb-T27 occurred an eclipse of one
OF earth's luminaries, one of those my ste.
rious celestial phenomena, very matter of
fact to the astronomer but o the general
public full of mystery aud wonderment,
and the source OF forBbodings, or deemed the
precursor o. calamity, by tue peoples abid
ing in the outer darkness of heatheDdom.
The lunar eclipse of last week was total,
The moon rose with the earth-shadow on,
partial eclipse beginning below the hori-
zon at about O'Clock, total at g.: l5 to-
tai eclipse ending at about 7; 40, the moon
emerging entirely from the shadows at
about 8: 40. The sky was obscnred during
the greater part OF the time, and interest in
the spectacle was therefore disapl ointed.
Later in the evening the clouds broke away
and the luminary shone out with exasper.
Rting radiance.
A references to these interesting, though
obscured, occurrences in the heavens above,
and the following explanation Of lunar and
solar eClipses, and discussion OF the general
subject, was prepared for the .ue OF the
WATCHMAN of last week, but Jrough some
perveTsity of fortune the Gu required for
the demonstration was not recet,eG in sea-
son. The general subject of sclipses IL,
however, Away timely and. therefore, the
article prepared for the occasion of the re-
cent obscuring of the moon ~ published in
this issue.
If the space wit'nin the circle described
by the earth in its quincy around the sun
level surface would be what the astrono-
mers call the plaue of the ecliptic, and the
course of the earth around the sun the cir.
Gle, of the ecipic, 40 called because when
either the sun or moon is ecipsed it is in
this circle; or, to come down to familiar
terrestrial things, the level area inclo-ed by
the circle of race course would be- the
plane OF the eClipic and the race course it.
self the circle Of the eclptic Locate the
sun near the center of this circle, the earth
h.. - fi.. 4 and
matter-of-fact idea is presented Of the as
Economical plane Of the eciptin, the circle
of the eclptic and the position therein OF
the earth and sun. To corhplete ths idea,
in its bearing upon the after of eclipses
imagine a secondary race course laid out
around the earth, aud the IN BON trotting
arOnnd that course at the same time tina
the earth is prfsuing It's way around the
main rack.
Now i the plane or level, Of this second
airy course were precisely the same AZ tina,
OF the main course, it is clear that when the
mooc in its race around the earth came
between the lat or and the sun the light
would be- shut off from the eaIth-the sun
would be eclipsed and when the earth was
between the sun and the moon the light
would be shut off from the latter-the
moon would be eclipsed; that IL, there
would BIS one eclipse of the sun and one Of
the moon in every revolution of the latter
around the earth-an eclipse of each every
the reason is that the plane, or level, of the
moon track, or orbit, is placed at consid
cradle angle with the plane OF the main race
course, or the ecliptc. In performing It's
Journey around the earth, the moon is there
fore one-half he time below tbs level of the
ecliptic and one-half above that level, 40 far
above or below tba it does not shut off from
the earth the suns RAYS when IT il between
the earth and the sun, nor does the earth
intercept the sunlight when it is between
the sun and the m non. Bu' twice in hat
journey the moon must iutersect the level
OF The main track along which the earth is
pursuing its way around the sun. II the
moon happens TO he between he sun and
the earth when IT. crosses the level Of the
main track an eclipse OF the sun occurs if
the earth is between the sun and the moon
a. the time o the intersection an eclipse of
the latter Occurs-an eclipse Of the sun
when the moon is new, OF the moon when
the latter is al the full. This will be made
clear by the accompanying diagrAm: