Evening star. [volume] (Washington, D.C.) 1854-1972, 1901-04-13
came that of nebula, and remains 90 to

came that Of nebula, and remains 90 to
| this day.
! The star OF 1912 CNova Aurigae) be-
| haved In similar manner to the preceding,
but a remarkable popularity presented it
self, which may have been present in the
4 spectra of the preceding stars, but II so
was overlooked since IN their cases only
visual observations were available. The
photographs of the spectrum showed that
each bright line OF hydrogen and helium
was not only greatly broadened, but that
1t had dark band Just above IL in the
spectrum; the violet is at the ''highef'
enu or the luminous scale. This phenome-
non can be accounted for by supposing shat
the light comes from two masses of hydro
gen or dluerent temperatures rushing past
each other with speed of several hundred
miles a second; It also, as we now know.
admits of different explanation as :he
effect OF a tremendous pressure upoa the
central portions of gaseous ball, sur
rounded by an outer envelope that is cooler
and less condensed. The spectra of several
Of the Novae detected by pilot pgraphy
showed the same popularity, but not all
of them, nor was it present i'm ;he spec
trum of the Andromeda star Of 1855. al
ready referred to. Our own Nova showed
and still shows it beautifully. although at
first, and until after II had passed it's
greatest brightness on February p, its
spectrum was that of an ordinary star OF
the so-called Orion type, showing only dark
lines mostly due TO helium and a few hazy
somber bands. But then in few hours
! there was rapid change and a complete
Transformation of the spectrum. The
widened lines of hydrogen shone out bright
with their dark companions by their sides.
and, in addition, with certain problematical
fine dark lines running through the center
of the bright ones As yet. however, we
have before us only n very incomplete
record of the various spectroscopic phe-
nCmeRa presented by the star, nor do we
know at present whether IL will will
not take the course of the stars OF 1875
and 1891, and end in the condition OF a
nebula.
Size and Distance.
AS to the real size and distance Of these
bodies We have positive knowledge. eX-
cept that in the few cases when they have
continued visible long enough-a scar at
least-to permit attempt at measuring
their parallaX. none could he detected.
They are veritable stars. probably COM
parable with the sun I'm magnitude. and at
distance hundreds Of thousands times
greater than our distance from the sun-so
remote that light takes years. perhaps CEN
turtles, to come to MS from them. The out
burst that we observed last February real
ly took place many years ago; how many
we cannot tell
That the observed phenomena indicate a
catastrophe of some sort is hardly to be
doubted. On the 10Th Of February photo
graphs of the region containing Nova Per-
sci were made at Cambridge, and render It
certain that then il was not brighter than
the 11th magnitude; II does not appear at
all the plate. Two days later. when
first seen and announced by Rev. DR.. An
derson Of Edinburgh Gt was also seen by
@ number of other observers the same
EVENING" 1t was little fainter than the
pole star. but brighter than stars of the
third magnitude, which are about 1000
times as bright as stars Of the eleventh;
on the oath 1t was nearly fifteen times as
bright as on the 2fst, and fully 10000 times
as bright as the eleventh magnitude. Then
1t began to fade and is now april p OF
the fourth magnitude, and about a thirtleth
as bright as its maximum. Its decline. as
always happens in such cases. is much
more general than its rise. When we in
quire into the causes of the phenomenon
we enter the regions of speculation and
find uncertain footing.
Views TO Their Origin.
In 1866 Higgins was inclined to ascrbe
1t to an action OF the same kind that
which produces the solar promfnences, but
on an immensely grander scale. The sun
is now completely surrounded by a thin
envelope composed mainly of hydrogen,
helium and calcium vapor. to which the
name of atmosphere has been given. and
from this enormous prominences ascend
from time to time to a height sometimes Of
two or three hundred Thousand miles and
with a speed of 100 miles or more a second.
These promnences show in their spectra
the same bright lines as do the temporary
stars and If by some volcanic paroxysm
the sun should suddenly cover itself with
such prominences, its spectrum would cer-
tainly be closely analogous to theirs
Zollner held a somewhat similar view
that the 'new star is really a very old
one, dying out and covered with crust or
fog that hid fits light until. from some
cause in a sort of dying struggle the outer
shell cracks open or is dissipated I'm trans
parent Vapor, and the internal fires blaze
forth only to die away again.
Due to a Collision.
But the view at present more generally
accepted is that the phenomenon is due to
collision of some kind; perhaps between
two stars though that is hardly probable
More likely ii may be the encounter of two
meteoric swarms as Sir Norman Lockyer
very positively maintains; or it may be. as
Seellger suggests, the passage Of a star
through such a swarm. The "twinning''
Of the spectrum lines which have de-
scribed is more simply explained by some
collision theory than in any other way,
though the Velocities, which IL is necessary
to assume in order to account for the OBJ
served duplication, are so enOrmOuS-from
500 to LOCO miles a secondhand creduIfty
is somewhat strained and staggered Still,
a matter of almost unuueStionable OBJ
servation we have among the spectre
scopic binaries," whirling walkers MN
Scorpii, for instance in which the reIa-
tive velocity of the two stars which revolve
around each other exceeds 300 miles a sec
ond Now. II by any means the orbits of
such q pair should be so altered i'm form or
diminished in size as to cause their at
mospheres to brush against each other, the
masses underneath would soon meet i'm col
lision, and something very like the outburst
of Nova" would certainly result.
But there are serious difficulties In the
way of all the theories so far presented
and much further study and careful discus
sions of observations will be needed to clear
the way to anything like real understand
ing of the subject.
THANK goodness. Easter is oyeri' WHY
so grateful?' "Oh, Harry and / always go
to church cross Easter morning; he never
likes my hat and never like his necktfe "