Delaware gazette and state journal. (Wilmington, Del.) 1883-1902, 1897-04-08
Winters Pictures Replaced by
Those of Spring.
VENUS AS THE EVENING STAR
Jupiter and Mars Also to be
Conspicuous.


quarter on. tho ODD. Sbe was in apo
gee nc 0 p. m. Saturday and will be in
perigee Mt A p. m. on the 18th. When
the moon ia nearest the earth, or in
perigee,s she ia 22l,6l4 and when re-
hottest, or. in apogee, 90, 912 miles
distant from us, quite a considerable
difference, which shows the eccenrricity
of the orbit. Wien we say that the
moons distance from the earth is 29S,
$50 miles. the average distance is
meant. and,this must be borne in mind
in regard to all the planets. The dis
tances OF the planets from the earth
must necessarily vary much, as the
planet 10 question. il an inferior one,
is at one time between the earth and
the SUB, position that is called infe
rior conjunction; at another time on
tho other side of ibes sun, a position
known as superior conjunction.
As TO superior planets, the orbits
OF which enyelop that OF the earth.
none. of course, can never come
between the earth and the sun, but
they may be either in conjunction aud
opposition. The moon. which revolves
about the earth, is sometimes between
the earth and the sun, or in conjunction,
and 10 this position is new; at other
times on the other side of the earth.
or in opposition, and then it is full.
The SUMS distance from the equator
was degrees 45 minutes and % seconds
north on the first and will be IA de-
grees 56 minutes and % seconds north
on the last, so that in courss OF the
month it passes through an arc of 10
degrees IL minutes. On the 18th of
April the apparent and mean times are
alike. In these articles we have called
the readers attention several times to
the earth's motion around the sun not
being perfovmed in circle, but in an
cllipss. and that, in consequence of
this and the inclination OF the orbit TO
the equator. apparent time is not and
cannot be uniform. To use such a
variable time for civil and business
purposes is wholly impracticable, and
for this reason mean solar time has
universally been adopted, which four
times a year exactly agrees with ap-
parent or sun-dial time. The 10th of
April is one OF those four dates when
correctly constructed sun.dial will in
dictate the correct mean time. The
difference between apparent time and
mean time is called the equation of
time. and is OF very great Importance.
The greatest discrepancy between these
two times takes place on November I'd
and February lltb, on which two days
the time indicated by tine sun-dial is
respectively l6 minutes 20 seconds fast
and IA minutes 80 seconds slow OF clock
time, during thesumtner the equation
of time can never be greater than six
minutes.
The planet Mercury will leave the
constellation Pisces and enter that of
Aries about the middle Of the month.
BY the end of Apgil it will be on the
boundary lines Of Pisces and Taurus.
| Venus will linger in Aries during the
| whole length Of the month and shine as
an evening star with that brilliancy
| that is peculiar TO her. She has still
a large eastern elongation and will not
set before little after o'clock during
the earlier part of the month. In
brightness Jupiter certainly comes next
| to Venus, and both these planets are
Internationally the two finest objects in
the evening skies. Tine great planet is
still in Leo and will set between and
O'Clock a. m. Nearly midway between
| Venus and JuDiter We easily recognize
the red.tipged planet Mars. Mars at
times is very brilliant, then vieing
with Venus and Jupiter in lustre, but
at present and for some time to come,
| though always n very conspicuous
object in the heavens, ii falls in bright,
mesa quite short of them. 1t is in
| Gemini and will set soon after mid
night Not long after 0 o'clock in the
evening Saturn rises with the constel-
lation Scorpio and when during the
summer months this fine constellation
occupies higher position in the
heavens Saturn will add very much to
its intrinsic beauty. The planets
Uranus and Neptune have changed
| their positions in scarcely sensible
degree.
The reader no doubt recolects that
the earth is not acomplete sphere hut
what is technically called an oblate
spheroid which is body generated by
the rotation of an ellipse about its
smaller axis The difference between
the equatorial and polar diameter is, it
is, true, comparatively small quantity,
&c miles; in fact small enough to rem
der calculations based upon the as
sumption OF the earth's being per
feet sphere in most cases sufficiently
accurate hut still it is sensible uuau-
thy Since th9 force of attraction on
objects on the surface of the earth de-
! ponds upon the distances from the centre
where for scientific reasons into which
it is not tho place hero to entor the
force of attraction or gravity may be
considered as concentrated it stands to
reason that objects cannot nave the
same weight on all points of the earth s
surface. For instance an object that
weighs 100 pounds on the equator
would weigh l9l pounds on the poles
This hattening al the poles OF the earth.
or, as it is called its oblateness, also
causes the lieuear length of degree to
be different 10 different degrees Of lati-
tude. Another name for obateness is
ellipicity which must not be con-
founded with eccentricity, term that
refers TO the distance of either focus of
an iellipse from the centre and which is
always larger than the obateness. The
determination of planets obluteneas
lisa very delicate affair and all attempts
atlohtaining reliable results have thus
far proved futile IN the case OF the
sun, moon, Mercury, Venus. the aster.
iods and Neptune. Saturn has the
greatest ohlateness of these that are
khowni then come 10 order Of magni-
tude Uranus, Jupiter. Mars and the
ea.th. which is mnre nearly spherical
than the others named.
Of the conspicuous consultations, 70
which in these articles we have con.
hnedourselves, that are on the meridian
about 0 O'Clock in the April evenings
We mention Leo and IIydes. Leo, or
the Lion, is a noble constellation, with