The Hawaiian gazette., 1875-02-03
Transit of Venus in Australia.

lCSull III piOul " INT plopIltlOTb.
Transit of Venus in Australia,
Our readers will be glad to learn that the
result of the observations of the transit of We
nus OF our own stations are highly Satisfactory
Three out of the four stations had beautifully
clear weather and successful observations. At
Sydney, the day was exceedingly fine and
clear; and the observations of the Observatory
were made with three powerful telescopes.
The ingress and egress of the planet were we'll
observed; but nothing like the phenomena of
the black drop, as decribed by the English as
tronomers, was seen; and the perfectly instan-
taneous breaking of it, described by the obser-
vers in 1863 was wanting Only one observer,
using most imperfect telescope, which was a
finder only to one of the larger ones, saw it as
described in books all the others saw the
planet gradually leave the suns edge at in
gress and meet the edge at egress and the
| phenomenon was not by any means so instan-
taneous as they expected. Most valuable OBJ
servations have been obtained, but the most
important results of the days work are the
photographs, of which about $50 have been
taken, showing the whole sun with the planet
on the disc, and $50 photos of the planet at
ingress and egress. !
AT Sydney, $50 photographs were obtained,
and some remarkable features noted, both at
ingress and egress. 1t was observed by Mr..
Russell, the Government Astronomer, that
when Venus was half on the suns disc the
other half of the planet could be seen on the
bright sky margin of the sun, and soon after
this the planet was seen to have a halo on the
side off the suns disc. This seemed about
second of arc in diameter, and increased in
brilliance as the planet crept on to the suns
disc. AT l2.24.29 the ingress was complete,
and the planet was wholly on the suns disc,
but no indication of halo or margin could then
be detected though the planet was examined
with powers up to 400.
At egress similar halo was observed. but
it was not so well seen. On the southern side
of the part of the planet which was off the
suns edge, definite white border was noticed, |
and could be distinctly seen until the planet
left the disc, and was lost in the brilliance sur
rounding the sun. Another popularity was
observed at egress the planet did not seem
uniformly black, but had specially on the south
side cloudy appearance. At Woodford 90
photographs of planet at ingress and egress
were obtained. The halo about the planet was
also distinctly seen at Eden; ingress was well
observed, but the cloudy state of the afternoon
only allowed the party to get forty photos, and
the egress was lost in clouds. At Goulburn
satisfactory work was done, but the results
have not been received yet
The photos thus obtained are ofimmense value to
science. Each one may be taken as an indepen.
dent observation of the planets position, and used
in combination with others in the northern hemis-
phere for determining the suns distance; and the
photos of ingress and egress will give the most sat
isfactory answer free from all personal bias to the
question, is there black drop, and at the same
time afford the means OF determining the line of in.
gress and egress to small fraction of second
One of our Melbourne kilograms contains the fol.
lowing information -" In referring to the transit
at the Observatory. The weather was wretehed
until close on noon, when there was break in the
cloud, and the first internal contact was obtained
1t was impossible to observe the first or external
contact on account Of the clouds The atmosphere
was splendidy steady in consequence OF previous
fall Of rain, and the definition of the phenomenon
is very distinct There was no appearance of a
black DROP The contact was clear and tangenti-
cal. Numerous photographs have been taken of the
ingress. They were taken rapidly at seconds in.
tcrvas, the great telescope being used as well as
the heliograph, but not quickly enough to obtain
ingress. The time was minutes IS seconds after
the expected time for the first contact"
Professor Hardness, of Hobart Town, reports ait
was cloudy at the beginning of the transit, and
that it then rained till half past When it after
wards broke away we began to take photos We
got SO of Venus on the sun; "A photos of egress
The contacts are all lostn
The first contact was distinctly seen by Dr.
James Anderson Of New York, stationed at Beech
worth.
Our Brisbane correspondent sends by telegraph
the following information =" Captain 0Reily, pri-
vate observatory reports in reference to the transit
of Venus He says that the day was favorable for
observation. There was no black DROP The
dark edge of Venus was illuminated for five min.
utes before internal contact Venus entered west
Of the sun with Eell-dehned round disc Attn.
gress thin greenish stream of light was between
her and the sun, the edge gradually becoming
brighter until Venus appeared complete circle on
the sun At Brisbane the mean time Of external
contact at ingress was not observed. The time OF
internal contact was 80 minutes 81 seconds past
noon; the middle contact, 9 hours Il minutes S.
seconds internal contact at ingress, minutes 40
seconds past l. External contact ingress, SO min
utes 10 seconds past l. neutral tint shade was
used with power l5O"-Sydaey Morning Herald