Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1891-03-08

MARS, MEBcURY, NEPTUNE, AND URANUS.
1t is difficult however, to realize that
| this can be the planet that aroused so deep
and worldwide an interest at his opposi-
| tion in 1888. His right ascension is hour
and SO minutes, his diameter minutes,
| and he is in the constellation of Aries.
| Mercury is morning-star until the 23d,
when it IS in superior conjunction with
the sun and becomes again an evening"
| star. He is now too close to the sun TO be
| seen with unaided vision. Even were the
| distance greater, the southern declination
| of the planet would render it almost i'm
| possible 10 pick hun out in the early twi-
| light. He is rapidly coming north, and
his size is also increasing very fast, so that
we shall soon be able to see him at his
best.
| Neptune is evening star, and we can get
q very fair idea of his whereabouts if we
look midway on line extending from tho
| bright star Aldebaran, in the eye Of the
Bull being pursued by Orion, to the Plei-
| AIDES. The moon on the 18th will also
| serve to mark the position of the planet,
as the two heavenly bodies are at their
| closest for the month at that date. Nep-
tune and Mars share the honor of being
| the only two evening stars as the month
| opens.
Uranus rises about 9:45 o'clock In the
| evening, but his position is such that he
| Is, astronomically speaking, morning
| star. The fact of his being in conjunction
| with the moon two days after it is full, al
though it might serve to locate the planet.
would not aid US in distinguishing it, as
| the very brightness of the almost round
face OF Luna serves to dim all stars in the
immediate vicinity.
ASCENSION AND pEc1IsATroN DEFINED.
| We find the terms right ascension and
| declination occasionally used in our at
| tempts to indicate definitely the positions
| OF heavenly bodies These terms are used
| in q way analogous TO that in which the
| position OF q city OF ship Is defined on the
| earth-namely, BY system of celestial lati-
| tudes and longitudes The measures which
| in the heavens corresponds most nearly to
| terrestrial longitude is called right ascen-
| sion, and that which corresponds to ter
| restrial latitude is called declination,
| The celestial meridian from which right
ascensions are counted is the one which
passes through the vernRl equinox or point
where the equator and ecliptic cross each
other. The right ascension Of any star on
| this meridian Is zero, and the right ascen-
sion Of any other star is measured by the
angle which the meridian passing through
1t makes With the first meridian, this angle
being always counted toward the east. The
declination of star Is its distance from
the celestial equator. whether north or
south. exactly as latitude on the earth is
distance from the earth's equator.
The earliest observers of the stars had no
suspicion of their true nature or of the dis.
tances that separate them from Us. II they
hands they supposed that they we're st
least, almost IN literal sense, accessible 10
the voice. Homer ssys that the hiehest
pines of Mt Ida passed beyond the
limits Of the atmosphere and penetrated
into thu ethereal region through which the
clsngor Of thu arms Of his hsroes roachsd
! 70 tho sU. This ~ ~ saolA hsmio.