The Norfolk weekly news-journal., 1910-04-29
AaIIey's Comet Is Approaching.

HalIey's Comet Is Approaching.
will likely not see again for d million
years will be staged in the vast hall of
space May IS, when Halley's comet,
on it's twenty-ninth recorded visit,
will pass across the face OF the sun,
shadowing the earth in its immense
but ethereal tail.
The transit of the sun by a comet
has been observed only once before
That was On September It. 1882, when
the great comet of that year passed
between the sun and earth. Though
the comet was so bright as to be visi
bic in daytime, it disappeared as soon
as it touched the suns disc. During
the transit, the observers at the Cape
of Good Hope could not discern the
comet even with their telescopes. For
some time they believed it had aban-
doned it's schedule and passed behind
the sun. 1t had gone in front of the
sun, however, the sunlight passing
readily through the head of the COM
ct, thus giving conclusive evidence of
its fleecy lightness.
1t is now seevral months since
Crommelin, the royal astronomer at
Greenwich, and Cowell, his fellow
worker, finished their calculations of
the orbit of Halley's comet. They
predicted that the comet will begin
to pass across the suns disc at 8
n
The earth will then be moving about
eitheen miles second in one direc.
ton, and fourteen million miles away
the comet will be kong about twenty.
five miles a second in the opposite di.
rection. Were the transit central, the
hour.
The Comet Light as Down.
According to Professor Frost of the
Yerkes observatory, the transit will
begin at 1880 o'clock and end at $50.
The computations are being continual
ly revised with a view to increasing
the accuracy of the orbit. These cal
culations are in charge of Professor
Leuschner of the University of Cali
fornia in com ection with the comet
committee of ne Astronomical Socie-
ty of America The comet passes near
Venus May 2, which will no doubt af-
feet the movement of the comet Con-
sequently it will be about May or
before the exact time of transit can
be stated with precision.
Such uncertainty is not strange.
The earth itself does not follow the
same orbit from year to year, in fact,
no planet ever moves twice in exact
ly the same path. The earth is very
large, yet the combined attraction of
the other planets is considerable,
enough to move the perihelion point
(the point in the orbit nearest to the
SUM so that the earth reaches it four
minutes and twelve seconds later each
year. In the case of Halley's comet.
the combined effect of the planets may
change its time of return to perihelion
by as much as five years. Jupiter
alone may change its period by as
much as seven hundred days. One
can get some notion of the relative
weight of Halley's comet and the
earth comparing four minutes and
twelve seconds with five years.
May Not be Seen Here.
1t is fairly sure that the transit
will not be visible in Norfolk, for May
IS the sun sets at 1904 o'clock. Obser-
vations will be possible on the Pacific
coast, where the sun, when the tran
sit begins, is nearly two hours high.
1t is, therefore, likely that good OBJ.
servations will be obtained with the
Lick telescope on Mount Hamilton.
The only large telescopes which are
really we'll located to observe the
transit are one at Manila and one
near Shanghai.
During the transit there will be no
dimming of the suns light, as in an
eclipse of the sun by the moon. Nor
will the comets passage across the
sun be as easily observed as a tran.
sit OF Venus or Mercury. May IS the
comet will be 14,300,0OO miles from
the earth. At that distance, accord.
ing to Professor Pickering, a solid
body seventy miles in diameter would
be visible in l5.inch telescope. That
such body exists in Halley's comet
is regarded by astronomers as very
doubtful Of c0uraa hodiaa ynuoh iaaa