The morning news. [volume] (Savannah, Ga.) 1887-1900, 1896-03-08
NEW DISCOVERY IN LIGHT.
SOLAR CORONA PHOTOGRAPHIC
BY ID. =. PATER.

Need 10 Wait for EcIipses-Cath-
ode Rays From sun sPOts-Bearing
Upon Our knowledge of the ORR
gin of Cyclones and Cold Waves-A
Powerful Aid TO solar Research.
Copyright
New York, March Close upon Prof.
Roentgen's sensational discovery, D. f.
! Packer OF South Birmingham. England.
announces another that has much similar
ity TO it. though the cathode rays Of which
it treats proceed from that great reser-
voir Of electric energy-the sun. Mr.
Packer has since July last, : been photo
graphing the suns corona in broad day
light. The results of this Photography
are said to be so remarkable that Mr..
Packer has withheld them from the pub
lie till this late date that he might test
them thoroughly; and it is not until now.
when he is convinced that his discovery
is a real one, that he makes announce
ment of it to his brother astronomers.
The suns corona, as is we'll known. can
be seen only during total solar eelipses.
when it shines out in soft, silvery beams
all around the dark body Of the moon as
she crosses the suns disk. 1t has been
the hope of astronomers that some way
might be discovered, so that it might be
seen or photographed in ordinary times;
but till recently all such efforts have met
with little success. Now, apparently, Mr..
Packer has succeeded.
The method is simple enough. 1t has
long been known that thin metal foil. or
metal films deposited on glass, will let
strong light through, though in ordinary
hf rt hn fa1a
opaque. Parker has now discovered that the
rays that do succeed in getting through
are the Photographic rays, in which the
corona is very rich, while the solar disk.
with all its glare, has relatively few of
them. He, therefore. simply photographs
the sun through one of these films and
gets picture of what no mortal eve
can see-the solar corona in broad day
light
The, Importance of this to astronomers
may be imagined when it is known that
they have not yet decided what the corona
IS Probably most of them agree that it
Is an envelope of very thin matter sur
rounding the sun, and shining either by
reflected light or electrically But it is
hard TO ind out anything about a thing
that can be taken clearly only once in
two or three years, and then for but a
few seconds Now, however, the corona
and its changes can be observed from day
to day, and probably Mr.. Parker has seen
have all the other astronomers of the
world since the dawn of time.
Packers first photographs were taken
with a camera of 4-inch aperture through
screens of tin and lead foil and sheet con-
per. Later he substituted a pin-hole for
the camera tense, with great advantage
at time some with the tense
and some with the pin-hole, and
the close agreement of detail showed that
the pictures were real, not the result of
some reflection or refracton in his in
strument. This was an important point
to prove, since his brother astronomers
markable results were probably unreli-
able.
The photographs thus taken show that
the streamers of the corona are very
closely connected with sun spots Every
sun-spot has its own ray; wherever a
a big sun-spot is sure to be found at the
bottom of it. The corona changes too
with the number of sun-spots This ac-
counts for the conflicting accounts of oh
servers at eclipses, no two of whom ever
saw the corona of the same shape and
size The reason is now seen to be that
its shape and size depend on the sun
spot from which the rays spring. Many
Of the most prominent rays are twisted
or spiral-a surprising fact, never before
noted, and at present inexplicable.
But the most interesting part of the
new discovery is the announcement that
It definitely proves the corona to be cleo
llGdi III lNA nature. II TINS IS so, every
sun-spot must be vast center Of electri-
cal disturbance, sending out visible RAYS
into space. The similarity of these to the
much talked of cathode rays will at once
attract attention, and the announcement
or the discovery, coming as it does close
upon Prof. Roentgen's is something of
coincidence.
Many astronomers have long believed the
coronal streamers to be electric, and have
compared them to those of the aurora:
but while the aurora is more like the
glow of a partially exhausted tube the
corona is like the cathode rays of a
highly exhausted Crookes tube. Prof Big
Glow, of the weather bureau of Washing
ton, has often pointed out the likeness
and those of electric of magnetic lines
of force, such as those in which view
filings arrange themselves when sprink-
led over a magnet. He thinks that thew
ultimately reach the earth, where thew
profoundly affect the weather origina-
ting cyclonic storms, cold and warm
waves, etc. The discovery of Mr. Packer
may thus put at our disposal the machine
cry for studying the causes that lie at the
root of all our changes of weather We
can already predict pretty well the prog
reSS of a storm when IL has once started.
we may now be able, by studying a series
OF corona photographs, to tell when and
where it will start.
These experiments are strikingly illus
trated by some performed recently by
DR.. Pupin, of Columbia, who obtained
an artificial electrical discharge, strongly
resembling the corona, from an elecfri-
ned brass sphere Enclosed in an exhausted