Evening star. [volume] (Washington, D.C.) 1854-1972, 1888-07-21
THE LUNAR ECLIPSE.
The Celestial Spectacle Which Will be
Observed Here III the Sky il Clear.
TIE TINE FAVORABLE FOR OBsERvATIoN-THE MOON
TO BE OBSCURE FOR LONG TIME-oBsERv ATIoSs
BY SCIENTISTS.

TIE TINE FAVORABLE FOR OBsERvATIoS-THE MOON
TO BE OBSCURE FOR A LONG TME-OBsERyATIoNs
BY SCIENTISTS.
Tomorrow night there will be a total eclipse OF
the moon OF more than ordinary interest on ac-
count OF the time at which it occurs and its dura
ton. The full moon Will enter the shadow OF the
earth, and its brightness begin to grow dull in
color at 1O:55 p. m, Sunday night, Eastern time.
IL Is not likely that there viii be any perceptibe
caangel IN the moons appearance at this time, but
II vii! gradually grow dul!er in color until IL :4 D.
H., when the total eclipse begins Then the entire
surface OF the moon viii become OF dark copper
hue and the last line OF light rim Will disappear
The moon Will remain in the plane of totally un-
I'll SO a. M, when 1t will begin to emerge from
the total shadow into the penumbra or outer
shadow. The middle OF the eclipse will occur at
Es;i3; ana the moon will leave the shadow finally
at 2:3o.
THE ASTRONOMERS.
This eclipse will not De observed here at the
Naval Observatory, for there is special work on
hand which could be aided thereby Last Janu-
ary there was a total eclipse OF the moon which
was regarded as highly important, because by the
precautions OF Russian astronomer q large
number OF observatorieS In Europe and America
TOOK observations OF certain stars noting the oc-
cuitations, or times or leaving The shadow for the
purpose Of determining the exact distances Of the
sun and moon from the earth. The results of the
observations are now being computed, and it Will
suits are reached. About the only work that Is
proposed on this eclipse Is at Harvard College and
PlttSDurg. Al the former place something Will be
done In the way OF photographiug the light from
the moon during the total eclipse, with a view OF
determining It's exact nature. This light of n
copper color, is that which Is reflected from the
sun, rays by the atmospheric dust particles and
other matter tnat nOatS around the earth,
MEASURING HEAT FROM THE MOON.
At Allegheny Observatory, Pittsburg, obserya-
tions Will be taken with the spectroscope that
may possibly give some data as to the actual heat
OF the moons rays that are reflected from the sum-
beams. Prof. Langley, now secretary of the
Smithsonian Institution, Is in charge OF this Oh
servatory, but the work will probably be done by
Prof. +. A. Very, his assistant there. Prof Lang
ley has done great deal in this line and has de.
vised an Instrument called the folometer which
registers wave lengths from heat when there is
really so little heat that II seems cold. He has
done finer work in this line than any one else
This instrument consists OF fine strips OF steel
that, by their expansion and contraction under
the effect OF heat cold, assist or retard the flow
OF an electric current and thus move the needle of
the gavanometers so 10 Indicate the exact degree
II has been stated that thOusandth OF a degree
Farenheit can be thus measured.
This eclipse will be the last visible here this
year. The moon Will be full and quite high in the
sky, so that the full benent OF the eclipse can be
obtained.