Evening star. [volume] (Washington, D.C.) 1854-1972, 1897-12-15
One Of the Largest Yet Makes Its
Appearance.
INTERESTING SOLAR PHENOMENA
Scientists Tell of the Huge Dimen-
sions Of the Spots.
MAGNETIC DISTURBAN Noes


The spot, according TO that eminent au-
thority, is so large that e world like this
could be dumped into IL, and no more ef-
feet be observed than dropping a pea in a
barrel.
Prof Hardness, astronomical director of
the naval observatory, said To TIE Star
reporter when approached upon the sub
jet:
me spots are appearing and disappear
ing continually. We did not observe the
spot out here. because We have beer en-
gagged in other lines of work hut we are
perfectly willing to give Prof Brooks
credit for his discovery. We do not find IL
necessary to look for the spots
The English observers are constantly
on the outlook for such phenomena. AMI
every twenty-four hours photographs are
taken Of the sun by them. In addition TO
the observatory at Greenwich there is
one at Mauritius. and another in India.
Ii would be utterly impossible to take these
photographs here in Washington. as there
is 100 much cloudy weather Ii such a
thing were thought essential an observa-
tory would have TO be established in some
other part of the country.
1T is nothing out of the ordinary for
spots of large size to be observed on The
sun. The diameter of the sun today is
about thirty-two minutes and 3D. seconds,
which is in round numbers Ss3.Sn miles
in diameter. The diameter Of the earth
in round hunters is about SpU miles
so that IL can be that a sun spot
equal to even 111th part of the diameter Of
the sun is large compared with the size
of the earth
Magnetic Disturbances.
Speaking in regard to the question as to
whether the magnetism of the earth is af-
fected by the appearance of the sun spots
or Har II IA
turbances had been noted at the observa-
tory lately. 1t is a yexed question among
scientists whether not the sun spots
cause magnetic disturbances, or vice versa.
1t is certain that the oscillations of the
magnetic needle have been very often
uced by the best observers coincdent with
the appearance OF large number OF sun
spots.
There is said also to be a disturbance in
the meteorological conditions, tending to-
ward lower temperature ami higher ba-
rometer.
Professor Hardness talked most interest
ingly on the subject of the sun spots All
scientists, though they may not observe
them personally. are attracted by their APP
rearance. The spot area H. estimated
TO cover from l25OD to 15O.so miles in
length, and in width $4,000 to 5000 miles.
Enormous Dimensions.
The dimensions of sun spots some
times enormous. Many groups have been
Observed covering areas of more than 1uo.-
ovi miles square, and the single spots have
been known to measure 10000 or 10000
miles In diameter, the central shadow alone
being 25.Co0 or 10000 miles across The
spot. however, measuring 10000 miles over
all would be considered large rather imam
small. An object of this size upon the SUMS
surface can easily be seen without a tel
escope, when the brightness is reduced
either by clouds or nearness to the HORIZON
or by the use of a shade glass. At the
transit of Venus in 1882 every one saw the
plaret readily without the telescope aid.
Her apparent diameter was about six or
seven degrees at the time. which is equiv
allen: to about 3l,HU miles on the solar sur
face Probably very keen eye would de-
tcct the spot not measuring more than
3,T0 or $4,000 miles. Hardly a year pass
es at time when spots are numerous
without furnishing several as large this;
SO that Ii is rather surprising than other
wise that there are not a greater number
of sun spot records in the pre-teleScopic
centuries The explanation probably lies
in two things-the sun is too bright TO be
often easily looked at. and when spots were
seen they would be likely to he taken for
optical illusions rather than realities.
During the years OF 1S11-s2 spots were
visible to the naked eye for considerable
portion of the time The largest spot yet
recorded observed in 1858. Ii mad a
breadth of more than 1i3 900 miles, near
ly eighteen times the diameter of the earth.
and covered about one-thrty-sixth the sur
face of the whole sun. Other extraordinar-
lily large ones appeared in 1S}2-'93.
Prof. Maunder of Greenwich observatory
wrote of the observance of sun spots coin
cident with magnetic disturbances on the
earth. He said that in a period of nearly
nineteen years. therefore from 1873 to 1882,
there were three magnetic storms which
stood out pre-eminently above all the 9TH
ers during that interval In that same
period there were three great sun spot dis
plays, counting the two groups of April.
1882 together. which stand out with equal
distinctness far above all other similar
displays.
Interesting Points.
Continuing. Prof. Maunder said it was
found that the three magnetic storms were
Simultaneous with the greatest develop
-nent Of the spots. He Gays:
rs there any escape from the conclu-
sion that the two have a real and binding
connection. Ii may be direct; 1t may be
indirect and secondary only, but it must
be real and effective
An important fact in regard to sun spots
is that the interval from what is known
as the minimum" which is the time
when the spots appear less frequently,
to the next following maximum" when
they are the greatest, is only about four
and half years on the average. This
is stated by one noted authority as
Economical subjects. He says that while
from the maximum to the next following
minimum is about six and six-tenths
spots springs up suddenly, but dies
away gradually.
Still another fact, as yet unexplained and
probably of great theoretical Importance,
has been brought out. Broadly speaking,
the disturbance which produces the spots
of given sun spot first manifests itself
in two belts about thirty degrees north
and south of the suns equator. These
belts then draw in toward the equator
and the sun spot maximum occurs, when
the latitude is about sixteen degrees; while
the disturbance gradually and finally dies
out at a latitude OF eight ten degrees
some twelve fourteen years after its
first outbreak. Two or three years be-
fore this disappearance. however two new
zones of disturbances show themselves.
Thus at the sun spot minimum there are
four well-marked spot belts. two near
the equator. due to the expiring disturb
ance. and two in high latitudes. due TO
the newly beginning outbreak. 1t appears
that the sun spot cycle is from twelve
10 fourteen years long.
While the periods between the mimi
num- and maximum" of the spots
is I OF exactly agreed upon by astronomers.
the fact seems to be certain that these
maximums and minimums do exist. BY
some 1t IL fixed at eleven years separa-
ttcp If &c stated that n this period is