The Houston daily post. [volume] (Houston, Tex.) 1886-1903, 1897-07-07
THE SKIES FOR JULY.

The SKIES FOR JULY.
The principal consultations now above
The horizon d; q. IN ARE the swan. or
No-,hera Cross. the Lyre and the Easl,.
IN he eastern quadrant O.; the heavens
Oph.lehgs. SAsi,ta-tls and the SCORPION IN
tAe south. Leo the Lion now setting 10
The West, the Great Boar. in midheavens
2 The Northwest and overhead The DRAGON.
Hercules Bootes and the Northern Crown.
The Swan tCynsusl is easily identified
from the ARRANGEMENT Of is siN brighter
stars in ;he form O: q 81. Andrews cross
The nor,hernmost Q: the stars. Alpha
Cyrui, kaown also as pencb. the Tail O."
is O, above the average Of second 'usenj-
,lde brightness and Is sometimes reckoned
among the first magnitude stars. The re-
naming i've are notceahly less brilliant.
being barely above ne third magnitude.
Deueb, as is name implies, IS in the
Swans tail the head is marked by the star
Beta. or the extreme right This star also
marks the foot OF The cross. The arms OF
the Cross form the Swans wings. The
swan lies in the ,hlck Of the milky way
and is one Of the riches, OF the coustella-
tons in stars visible or invisible TO the
naked eye
Alpha Cyneri is one OF the ten brrlan,
stars Of the Northern hemisphere, upon
which Or. Elkius 4 few years ago made
series OF observations with the Yale col
lege heliometer for the purpose of ascer-
tanning their distances from Us, and It Is
one OF thos.-Ar'.lrus being another of
which The paraliaN' proved to be a guam
uiy so minute ;ha, no TRUST worthy meas
uremont OF it could be obtained bright
as The star Is, IL is apparently plunged in
space to a depth unbelievable by any
means now available to Astronomers. and
we must regard it as one Of those stupen-
dous suns by the Side OF which our own
brilliant luminary would become a mere
pygmy,
The star Beta is beautifully coored
double star sufficiently wide" to be sep
arated by even n small telescope. Its com
pon"nts are yellow and deep blue. II is
the most splendid object of its elias in the
entire heavens.
star which though of only the nth
magnitude, is Ear more interesting than
either Of the stars just mentioned, 81 Cygni
famous as the first of the stars to surren-
der tho secret OF its distance. or rather
nounced. by Bessel. some sixty years ago
Tho star is visible to the naked eye. and
can easily be found from its position at
one corner OF four sided figure, of which
the three other corners are marked by III,
three lower stars of the Cross \ little
triangle OF stars. brought out very pre;tily
Win an opera glass. will be found here
The star in question is the uppermost Of
the three which form the triangle 4
telescope which magnihcs no more than
twenty 10 thirty times Will show II TO he
II double star. its componcnts being OF
ABOUT me same brillianoY and both Of 4
deep grange color
star distances are determined by meas.
uring the amount OF change which takes
place IN the position OF a star with ref,r
thce To Its neighbors In consequence of tha
chanee IN our point OF view. in The rourse
Vi me year due To the revolution of he
earth in its orbit round the sun. The d.
ameter OF the earth's orbit is ,bo,t is
Uoo'VpO miles. In the course OF the six
months required by tho earth to so half
NaN around this immense circle our rCsi.
hon III space changes. of course IN ms
extent suppose that at the beginning o,
tHe GIN months two stars, one of which is
comparatively near us, while the other is
almost infinitely remote. are seen 10 he
very nearly in range with each other. Then
at lhe end Of the six months the raupe
VIII not be precisely the same; tho tvo
stars VIII appear a liitle closer together or
mite farther apart. as the case may no
ihe nearer star having moved apparently,
ana the nearer 10 us IL l. the greater viii
Do mo amount OF this shit OF position
OF parallaX, as it is called This liz
inc quantity which the astronomer a,nIin,
10 ma the stars distance must MEASURE.
10 give some idea OF the difficulties IN.
vowed m he measurement Il may be sslid
mat no star has yet been found OF which
me n1fdllaN or annual shift Of position is
so large as one Second Of angular ,1eas"
ufemeni' one second is the anglo included
between two straight lines which. starting
AT common point, diycree so slowly that
az distance OF three and a quarter miles
IheS arc but one inch apart In order liar
iheS should diyerge 10 a distance equal 10
inc rialus OF the earth's orbit--for II can
% SHOWN economically that the 'parallaxn
q star is the angle which would he sui.
'ehaed by the earth's orbit, viewed from
the Instance OF the star-thSse lines ,nust
nave length Of about 20 600 900 ntilss
ms would, therefore. be the distance NJ
,he star q which the parallax was one
second That OF sixty -one Cygni rs ,css
imam haif second. and its distance ac-
eoruihsly Is moro than forty million million
miles. or. in round numbers, 400. 600 times
ue distance Cd the sun--a distance tray
ersed by light In about seven years,
stars distance being known, some
Idea may be formed OF its size frpm tho
hrllliancy OF Its light, II has been esti-
mated that the combined masses OF The
TWO bodies which form tho star Gil cyeni
would make . single sun about hall az
massive as ours. which in their uiace would
shiae e star OF the third nagnitude. III. a
4tst tLtfi"n zet In this ease hou s.var