SOUTHERN ASTRONOMERS and
AUSTRALIAN ASTRONOMY
AURORA AUSTRALIS.
By H. C. RUSSELL, B.A., C.M.G., F.R.S.
[Read before the Royal Society of N.S.Wales, November 3,
1897.]
• Numbers in [ ] brackets are the original page number from
source.
Written :
GENERAL INTRODUCTION
AURORA AUSTRALIS.
INTRODUCTION
WITHIN the last few years associations of persons,
interested in the study of auroral displays have been formed, in the
countries which surround the North Pole, with the common object of
investigating the phenomena presented. Many new and important already
been brought to light, and something has been done towards connecting
the phenomena about the North and South Poles. I have done a little
by collecting and publishing the reported Aurora Australis, but I
feel that what has been done is not enough, and that if these records
are published in our Society’s volume
that they will reach a much wider circle, and further will, I hope,
lead all those who see the Aurora Australis to report it.
Sailor generally believe that the Aurora is a sign of coming bad
weather, and they are keen observers. Nearly all the information
about displays come to me in ships’
logs, but we want also the help of those on shore who are in good
positions for observing. Two of the auroral displays in April this
year were unusually magnificent, and one of them which I want to
bring before you this evening was the finest ever seen in the
southern hemisphere, so far as I have been able to ascertain.
This was observed by Capt. Campbell Hepworth, R.N.R., of the
R.M.S. Aorangi, who sent me the following description of what
he saw, which reads more like the description of an aurora seen in
the far north by arctic observers, than what we should expect to be
seen between the Cape of Good Hope and Australia, where the Aorangi
was in 96° East and 47½° South, when the aurora was seen
:-
“BRIEF NOTES OF A FINE AURORA SEEN
ON APRIL 20, 1897.
It was first seen as a diffused light over the southern horizon,
like the light over a distant city which is illuminated by electric
[2] light, from this light flashes or rays soon shot upwards, and in
every direction increasing in length and brilliancy, until at
7·30 p.m., they were shooting across the sky to within 30°
of the northern horizon. Cones and circles of light travelled rapidly
over the whole sky, and flashing beams of intense light darted from
one to the other. This continued until 8·30 p.m.
A remarkable change then occurred, the sky being cloudless, moon
and stars shining brilliantly ; an arch of bright green light, fading
oft into yellow, formed over the southern horizon rose rapidly to a
higher and higher altitude, and was followed by similar arches in
regular succession, until there were six arches quite distinct, their
apices being from 10° above the southern horizon to 60°
above the northern horizon ; these arches appeared to be formed of
vertical bars of light side by side, thus building the arches of
light, which varied in width from 5° to 20° each, and all
of them were bright green and yellow at the tops of the arches, and
of a rosy hue where they touched the horizon. Subsequently these
arches changed their shapes in all parts of the sky, forming
remarkable bands of light, and in some cases patches of light, which
in all cases seemed to be fragments of the original arches, from the
curves they presented, with the exception of two places, where the
bands seemed to meet at right angles.
Up to 8·30 p.m. the flashes of light which came from the
southern centre of action seemed to shoot along the eastern horizon,
and then rise up like bands of light on hinges at the north and south
points of the horizon, sweeping across the sky to the west ; after
8·30 the flashes of seemed to shoot vertically upwards. A circle
of light about 30° in diameter now formed about the zenith, and
the rays of light before referred to seemed to rise up to the circle,
but did not touch it exactly at right angles, but slightly
tangential, so much so that they suggested the picture of a cyclonic
centre with winds blowing tangentially round it. 1.
[3]
Pendent overhead one could see the cloudless blue in the centre of
the ring-shaped tassel of coloured light. Later a spiral cord of
light, shewing three perfect coils formed at the zenith, and look the
ring of light, travelled westward, while to patched of brilliant
light, spiral in form like a waterspout, were flaring in the
west.
The barometer had been at forty-eight hours prior to the display
abnormally low, between 28·90′ and 28.80′ (Board of
Trade Barometer) and the wind from W.N.W. strong. A fresh to moderate
gale had been blowing previously.
In the midst of the grand display just recorded, a remarkably
bright meteor, starting from Canis Major in the north-west, travelled
slowly across the sky to the south-west, discharging at intervals
fragments of colour, and thus adding to the splendour of the scene, A
special feature of the display had a motion to the west like a
changing panorama. after 9·15 p.m. the aurora was less
brilliant, but burst into greater activity a few minutes afterwards,
more especially in the northern semicircle. The display lasted until
9·45, gradually fading after 9·30 p.m.”
This short account was prepared by Commander Hepworth hurriedly,
while he was getting ready for the first voyage of the new service
with the Aorangi. He expressed his intention of sending a fuller
account of the aurora to the Royal Meteorological Society, London, as
soon as he could find leisure to write it.
In the mean time the third officer of the Aorangi, with the
permission of the commander furnished me with the following account
based on his own observations while on the deck, and those of the
chief, third and sixth engineers who were very much interested in the
aurora.
Mr. Bayldon, third officer, says, “Herewith I send to you our account of the
aurora. It is compiled from the notes I made at the time whilst
actually watching the scene, and from an account written next day,
and it has been overhauled by our chief, third, and [4] sixth
engineers, who were all interested spectators, and nothing in the
account was allowed to pass unchallenged.”
In conference with Mr. Bayldon before he wrote the account for me,
I asked him if possible, to compare what he saw with the pictures
given in “The Aurora Borealis,” by Alfred Angot (1896 London), and the
references are to the plates in that work.2.
He says, “If the arches in the
frontispiece were more regular they would fairly well represent the
rising of our arches, but ours were much farther apart, and were most
perfect when near the horizon. Figures 2 and 3 resemble the bands of
light which we noted before 8·30 p.m., but ours were much
fainter, and moved from east to west as if they were arches pivoted
at north and south points. Figure 6 resembles many conditions we saw
after 8·30 p.m., while figure 7 fairly represents the rays we
saw radiating in all directions from the southern horizon, though
with us they did not radiate with anything like the regularity and
profusion shewn in the diagram. Figure 8 resembles very many patches
of auroral light which we saw after 8·30 p.m., excepting the
dark lines, which we did not see. The lower point of No. 8 might
answer to what we have called a water spout. Figures 12, 13 and 14
(without the hook) were many times illustrated, especially in the
circle and spiral chord, which we have described, though we saw
nothing approaching figure 13 in grandeur.
“There is one feature of the
illustrations which strikes us all as very different from what we
saw, and that is they all shew the lower edge of the arches as
defined and the upper one as shading off into drapery. In all that we
saw, this was reversed ; with us the upper edge was defined and the
lower edge shaded away into drapery.
“The aurora first became visible at
6·30 p.m., on April 20th, 1897 (apparent time at ship), as a
bright diffused light in the southern horizon, above a heavy bank of
cumulus, the sky being perfectly elsewhere and stars shining
brightly. Soon separate and beams of light flashed from this
diffused light in every [5] direction — horizontally,
vertically, and obliquely-like electric search lights
increasing in length, breadth and vividness until, at 7·30 p.m.,
the vertical beams reached to within 10° of the northern
horizon. Faint beams of light during the same time also formed in the
east, and swept rapidly across the entire sky from east to west,
passing through the zenith and reaching from the southern to the
northern horizons. Cones and patches of intense bright light also
appeared in all directions, discharging beams and flashes of light
incessantly from one to the other, like electrical discharges or
lightning. This continued until 8·30 p.m. The moon rose at
7·18 p.m., and every particle of cloud disappeared, the night
being very bright and clear with moderate north-west breeze.
Barometer 29·00; thermometer 44°.
“At 8·30 a most remarkable
change occurred ; until then the aurora had been simply composed of
white light of homogeneous structure, now colours and hues of every
description appeared suspended vertically in the sky. A narrow
arch– the upper edge perfect in outline as a rainbow, the lower
edge serrated and fringed, owing to the difference in length of the
beams or bars of which it was composed-suddenly appeared 15°
above the southern horizon of rich green and yellow hues, and rapidly
rose to a higher altitude. Another of the same description formed and
followed it, others followed in similar order until there were
distinct arches of drapery, the first tier then being about 60°
above the northern horizon. They were long narrow arches from 5°
to 20° wide and made up of vertical stripes and streams of
light, like Mr. Angot’s frontispiece,
which were suspended in a pendulous position in the sky, the upper
half of the drapery being bright green and yellow, while the lower
half was of pink and roseate hues. Rapidly the arches changed and
contorted into fragmentary scrolls of many shapes ; in all parts of
the heavens other such formations appeared cloud-like and evanescent
to north, south, east and west, in some cases lasting only a few
seconds, in others for a minute or two ; all of the brightest green,
yellow, and roseate [6] hues, changing their shape and position with
almost inconceivable rapidity. Dark arches also were visible.
“When any such drapery appeared
directly overhead, only a gorgeously bright, very narrow, sinuous
line was presented, but when viewed obliquely, the fringe-like depth
of the scroll, with its different shades of colour was most
beautifully apparent. Every formation was arranged in some sort of
curve or spiral (excepting two which formed two distinct right
angles); every one directly it appeared darted away to the westward,
and in every one there appeared to some observers to he a rotatory
movement amongst the coloured particles of which the drapery was
composed, whilst to others this movement appeared to be wave-like 5
horizontal flashes continually darted from one nebulous mass to
another. To add to the splendour of the scene, at 9·10 p.m. a
remarkably bright meteor slowly passed across the western horizon
from Canis Major, bursting into many coloured fragments and passing
underneath several of the fragmentary parts of the aurora.
“In such an extensive and ever
changing panorama it is impossible for one observer to accurately
describe the many interesting aspects which so continually presented
themselves, and so rapidly vanished. Each one would catch a glimpse
of something different, and could only form a very general idea of
what actually took place. However three formations were so brilliant
as to be noted by all— First at 9p.m., when a magnificent
circle of light appeared directly around the zenith, with a diameter
of about 20° formed as before of draped rays of beautifully
tinted light. Looking upwards through this circle it was plainly seen
that these rays were not strictly perpendicular, but slightly
slanting downwards from left to right, and the rotatory or wavelike
movement of every particle was most apparent. Secondly at 9·5
p.m. when a spiral scroll of three chords arranged itself around a
nucleus of a few degrees towards the northward of the zenith Thirdly,
at 9·15 p.m., when two forms of exceptionally bright light
appeared like waterspouts 10° high in the western horizon, which
was probably a perspective view of a sinuous line reaching below the
horizon. [7]
“After 9·17 p.m. the scene lost
much of its brilliancy only to burst again into magnificent activity
at 9·20 p.m., being brightest and most intense in the northern
semicircle, and lasting until 9·30 p.m. After this the splendour
gradually faded away, through occasional discharges of bright flashes
or the appearance of clouds of diffuse light continued until
9·45 p.m., again being homogeneous nature.
“Generally throughout the display,
first magnitude stars were visible, shining through the aurora,
though at times is brilliancy was so radiant as to totally absorb
their light. The moon was bright with no halo around. After 10 p.m.
the sky rapidly clouded over with cirrocumulus and cumulus, and
slight rain fell the breeze falling very light. Throughout the
previous day (April 19), the weather has been cloudy and unsettled,
with a fresh north-west gale, which gradually moderated on the 20th.
During the night of the 20th, moderate to light north-west breezes
prevailed. At 8 p.m. on the 21st the wind rapidly freshen to a
moderate south-west gale, which continued until the evening of the
22nd.”
A second display of the Aurora Australis was witnessed from R.M.S.
Aorangi throughout the whole night of April 23rd, 1897, from
7·15 p.m. until 4 a.m. April 24th, the ship being in Lat.
45° South, Long. 119° to 121° East ; barometer
30·25 ; thermometer 45 °F. Owing to the sky being so
cloudy, with cumulus and showers occurring at intervals, but little
could be noted of this aurora. A diffuse light prevailed over the
southern horizon throughout the night. At 9 p.m. two arches of more
intense light appeared above the former southern horizon at the
altitudes of about 20° and 45°, they were of a pale
greenish hue. At 11 p.m. bright flashes in a vertical direction were
apparent for a few minutes, all in a homogeneous structure.
Throughout April 23rd, the wind was gradually moderating from a fresh
south-south-west to light southerly breeze at midnight. At 8 a.m. on
the 24th again freshened to a moderate south-south-west gale which
continued until noon of the 25th. [8]
LIST OF AURORAS 1896-7.
Date. |
Name of Ship, |
S. Lat. |
E. Long. |
Notes. |
Aug. 21, 1896 |
Hawkesbury |
48 2 |
100 21 |
Aurora australia at midnight |
,, 22, ,, |
,, |
48 1 |
101 20 |
Aurora at 4 p.m. |
,, 23, ,, |
,, |
47 49 |
106 31 |
Aurora at midnight no other particular details
given. |
Oct. ,, |
Thermopylæ |
46 44 |
114 06 |
At midnight the aurora was very vivid. |
Jan. 2, 1897 |
Damascus |
48 9 |
107 10 |
Aurora australis visible. |
Mar. 1, ,, |
Hawkesbury |
51 4 |
73 49 |
Ditto ditto. |
,, 5, |
,, |
51 34 |
93 53 |
Ditto ditto. |
,, ,, |
,, |
51 42 |
95 23 |
Ditto ditto. |
April 20, ,, |
Aorangi |
47 25 |
96 40 |
Special notes in text |
,, 23, ,, |
,, |
45 0 |
119−121 |
Ditto ditto. |
Aug. 1, ,, |
Damascus |
46 0 |
108 40 |
At 8 p.m. cloudy, Aurora australia visible. |
Endnotes
1. This is more like the Aurora
observed in Melbourne 2/9/1858, than any other I know.
2. See https://
archive.org/details/auroraboreali00angouoft
Last Update : 4th January 2014
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