Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1885-03-29

April ANoNc TIE rLANgrs.
.r,.,,mesn Or sse Pssssissi HeaveaIy
asSsss-Psssspce ana an opers-Gisss-
Tsree Evensa

asss.s-Passsnce and sR Opers.Gisss-
farce Eves,&
providence Journal
MERcuRy is evening star until the
9th, when he becomes morning star.
lie comes to the front on the planetary
records, easily winning the place Of
honor, for he is the only member Of the
suns family who contributes interest
ing incidents TO the annals Of April.
the month being specially uueventful
and monotonous as regards the move
mcnts Of our usually lively and active
byothcr aud sister planets. Mercury's
course is marked by three events.
The most noteworthy TO terrestrial
view is his greatest eastern elongation.
This event occurs ON the 9Th at 2
o'clock in the morning, when mercury
is 10 degrees 20, cast Of the sun.
II is the best opportunity the year az
fcrds for sight OF Mercury as evening
star with the unaidcd eye. Intelligent
observers will be sure TO find him, IL
the weather conditions are favorable
and If the directions given are faithfully
carried out.
Three conditions are required for
best conceivable view OF Mercury "a
eastern elongation. The event must
take place at the season Of the year
when twilight is shortest, in order to
have a darker background TO the sky
for the exhibition. The planet must
he in sphelion, or farthcst from the
sun, in order TO have the elongation
or distance from the sun the greatest
possible. The planet should be at his
greatest distance from the ecliptic, or
suns path, on the north side, neces-
sary condition for the best observation
Of all the planets.
These three circumstances never oc-
cur together, for such is the position of
Mcrcury's orbit that when the elonga-
ton is the greatest possible the planet
Is south Of the sun and not so we'll sit
mated as when the elongation is less
and the position north of the. sun.
We therefore never see Mercury under
the most favorable combinations. At
the present elongation the twilight is
near the shortest and the position OF
the planet is at his greatest distance
north of the suns centre, or north of
the elliptic. But the elongation is
10 degrees PC minutes. instead Of the
maximum, 81 degrees AZ minutes, and
he is. therefore, far distant from aphe-
lion. which, even travelling with his
amazing velocity, he will not reach
until the 18th Of May. 1t will be re-
mcmbered that Mercury, as seen from
the earth, appears to oScillate in straight
lines east and west of the sun, and that
at eastern elongation he has reached the
end of the chain that seems to bind him
to the sun, and then begins to retrace
his steps. The ellipticity of his orbit
is greater than that Of any other planet
in The system, so that at aphelion he is
l5.000,000 miles farther from the sun
than when in perihelion. There are
the same great variations in his distance
from the earth, and corresponding yaria-
tions in his brilliancy.
In spite of these drawbacks, the
smallest and swiftest Of the planets will
be a charming object in the early eve
ming sky from the beginning to the mid
die Of April. No other planet is like
him. Not fixed star in the sky can
bc compared to him in brilliancy when
seen under the same light, unless 1t may
be Sirius, which he somewhat resem-
bles, shining with brilliant white light,
though we have sometimes seen him
take on a golden aspect, and often a
rosy hue. Easily as he may be seen in
this latitude, it is almost impossible to
detect his presence in the central and
northern regions of Europe. 1t was a
lifelong sorrow TO Copernicus that he
never had glimpse of the swift-footed
planet that travels nearest the sun.
We give Mercury's position at
eloDgation, though he will be visible
for eight OF ten days before and after
the epoch. On the Sth he sets about
& o'clock, nearly an hour and three
quarters after the sun. The best time
for observation is three quarters of an
hour after sunset, or I o'clock. The
planet will be found northeast Of the
sun, about Q degrees north of the sunset
point. The observer must command a
view Of the northwestern horizon. the
sky must he cloudleSS, and the atmos-
pherc clear. There are no large
stars near him, but he will be plainly
visible 70 those who look in the right
place. Patience and an opera-glaSs are
valuable aids in picking him up. Even
when found he is easily lost, hiding
himself in the twilight glow, and then
suddenly reappearing, as if taking a
conscious pleasure in battling the curl
oSity of those who are earnestly seeking
TO behold his face. Audacity is the
prominent characteristic Of the smallest
Of the planetary brotherhood. The
most painstaking observer has not sue
cceded in finding out the cause of the
undue acceleration of his perihe-
lion point, and it is general
Nv conceded that the science OF
astronomy has at present no means
capable Of solving the problem. lie
pcrsistently hides from view any small
planet OF planets revolving nearer the
sun than himself, though astronomers
have travelled many thousand miles
hoping 10 discover intra-Mercurial
planets during total solar eclipse, and
he manages 10 keep the secrets OF his
physical organization hidden within his
own domain or in the dense atmosphere
that probably surrounds his solid crust.
We know with certainty little more
about him than when the telescope was
first invented. Amateur astronomers
with ordinary telescopes have seen bright
spots on his surface indicating an axlal
rotation Of about twcnty-iour hours
blunted cusps or horns, interpreted as
due to the shadows of mountains eleven
miles high--a deviation from spherical
form--and even hole through the
centre. Practical astronomers, with the
most powerful telescopes in the world,
fail 10 see these marvels on the disc OF
our feet-tooted brother, and give little
credenee TO them. Nearly all that IS