Evening star. [volume] (Washington, D.C.) 1854-1972, 1899-08-12
SKIES IN AUGUST
Northern Cross is the Finest of the
Summer Consultations.
SCORPIONS GATHERING STARS
What Forms the Meteors or
"Shooting Stars"
THE PLANETS OF THE MONTH
Written for The Evening Star.

Written for The Evening Star.
One of the finest of the summer constel-
iations is the Swan (Cygnus) or Northern
Cross. At about 0 o'clock it may now be
found well up toward the zenith a little
north OF east. Its six brighter stars form
a large st. Andrews cross; if the lower
most star is omitted the remaining five
form a cross of the ordinary type.
The brightest of these stars-that on the
extreme left-bears the Arabic name Deneb,
the Tail 1t marks both the tail of the
Swan and the head of the Cross. 1t is
usually classed among the first-ma gnitude
stars, though considerably below the aver
age brilliancy of stars of this class in Or
der, apparently, to make the number of
these star exactly twenty-ten in each hem
isphere. This is one of the first-ma gnitude
stars of which DR.. Elkin few years ago
failed to detect any parallax-that slight
annual displacement of a star on which
may be based a calculation of its distance,
and the star is, therefore, presumably so
enormously remote that it must be regard
ed as one of the celestial giants, probably
far SURPRISING in size the more brilliant
Dog Star.
Lying in the thick of the Milky Way,
the Swan is one of the richest in stars
visible or invisible to the naked eye, of
all the consultations. Even an opera glass
Will oring out here hundreds of little twin
klers which cannot be seen with the naked
eye. Particularly rich will be found the
region lying just north of Deneb.
The star in the foot of the Cross-the
beak Of the Swan-is Beta Cygni, one of
the most splendid of the colored double
stars. 1t consists of a bright yellow star
and a smaller companion, which is deep
blue. 1t is a particularly fine object for a
small telescope, and, indeed, 1t can be seen
fairly well with an ordinary spygass,
which magnifies twenty or twenty-five
times.
small circle on our planisphere N arks
the position of star in this constella; ion,
which, although of only the fifth magni-
tude, is one of the most interesting of the
stellar host, 81 Cygni, famous as the first
of the stars to surrender the secret of it's
distance from US. Note that 1t forms with
Deneb and two other stars of the Cross a
four-sided figure, of which the sides have
nearly equal lengths. 1t is an orange-col-
of ffth-magnitude stars, easily seen here
with the naked eye and brought out very
prettily with an opera glass.
Cygni Is Far Away.
The distance now assigned to 81 Cygni is
about 100000 times that Of the SUM- dis
lance traversed by light in seven and a
quarter years. The star is double, and per-
haps some idea of its enormous remoteness
from US can be formed, even better than
from the figures just given, when it is said
that, though to the naked eye, and even
through an opera glass, it appears as a sin
gle star, Its component suns cannot be less
than 5000, 900, 900 miles apart. Yet this star
81 Cygni, is the nearest of the stars with
one exception, so far as has yet been ascer-
tanned. The sun removed to its distance
would appear a star about as bright as
Deneb.
Directly above the Swan and nearly over
head is Vega, in the Tyre, one of the bright
est stars in the northern skies. Just be-
meath it may be seen two stars of the fifth
magnitude, which form with it a small
equal-sided triangle. The more northerly
of these faint stars Is Epsilon Lyrae some
times called the 'double-double Even an
opera glass will show that this is a double
star-indeed. very keen-sighted person can
see it elongated with the naked eye, while
a telescope of moderate power will show
that each of its components is also double.
This star consists, in fact, of seven COM
ponents. although to see the faintest of
them requires fairly large telescope.
Southeast from Vega, little less than
half way from 1t to the horizon, is Altar,
an average first-magnitude star in the
Eagle. 1t is f1anked by two smaller stars,
which perhaps formed originally the Eagle s
wings, and which will aid in identifying the
star.
At the left of Affair, forming with 1t and
Beta Cygni a triangle, of which two sides
are about equal, Is a cluster of six or eight
small but sparkling stars, known anciently
as the Dolphin, but which now bears the
rather dismal name, Jobs Coffin. This is
one of the prettiest of the small constella-
tions and is fine field for an opera glass.
Turning now toward the south we have
before us the consultations Ophiuchus, the
Serpent holder, together with the wriggling
Serpent which he holds, the Scorpion and
the Archer, Sagittartus. On clear, moon
l., t. he anctc l. linz
of the summer skies. Through it's midst
runs the Milky Way.
The Scorpion glitters with stars Of every
magnitude. At it's center stands the ruddy
pion's Heart" At the right of this star
may be seen the Scorpions claws; that is,
it's original claws, for astronomers have
robbed the Scorpion of one OF its claws and
have placed it in the Balance Q4ibra), while
on the left may be traced the tail. curving
downward and terminating in pair of
third-magnitude stars, which form the
sting.
Visible Through an Opera Glass.
The third star below and to the left of
Antares-marked NJ on the planisphere-is
Mu Scorpfi. 1t can be seen by a person Of
good eyesight to consist of two stars very
close together. 1t is a fine opera glass OBJ
ject The upper star of this close pair is
interesting as one of the five "spectroscopic
hinaries," which have been discovered at
the Harvard College observatory. That is
to say, it consists of two stars revolving
one about the other, but which are so close
together that they cannot be seen separate
~ with even the largest telescope. The
spectroscope has revealed them through
the periodic doubling of the lines in the
spectrum of the star. The period of their
revolution Is only thirty-five hours-the
shortest period known in the case of a deu-
Bile star.
Eastward of the Scorpion may be seen a