New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1904-10-23
STELLAR NOTIONS.
Discoveries By the JfaIs Erped;,;o.
IN Chill.

AZ iro,,l. -, ms interesting and inpo-fa74 d.
the 49, -. me astronomer is the rate al 49,
with the facts the slleeestfo, e.. . Unfamiliar
are not stationary is triae p-zzllo, r4 D'ise1F
~ io"k ago asceTtained that practtq.,1,-. 4, - ~
eHl are Shitting their positions To
-, '"e'e ~ ans hing systematic in ,br-
AaVior Or whether each star Is Avia ~ -
space on an independent course 4, a. -I "a 'oush
coiiect information regarding n i7-po -. =
the" ami "a make two kinds ~ ,,e. %
~" results OF which can afterward be eor,5i..s
~ N.'.la'lon OF celestial latitude and Irngf,r,
Is caled The proper notion OF a srs- - ,s
learned BY the comparison Of r.-,~s. - ,'' /" e
terVais OF several years Visual obee--.,,, m
P"OtosIdphy furnish the necessary data o. '
puuus 'he movement at right angles Ia W.. ~
: GO 'or 2 long time the star nlnnba-.s
=. S''oOIloFldses catalogue. called the PM
away haG the reputation Of having the 49,,
proper motion-about a hundred and SIT ,,rs-
Secoh0' TO md out whether a celestial 80, E,
moving away from or toward the earth 49,.
iue'Hou - employed Several observations ar. a.
slrable. so that the average NAV be 49,
aiso LOT 0tneF reasons which win be- rlent,o,.s
presently But It Is usually possible n as.s-.-'
the facts within few DAYS or weeks - -
purpose the body IS examined with a s7a.tro,
""ton y 4tlaehed 70 telescope. The positions.
which the tiny cross lines on the ribbo-,iE. -.
uum OF a luminous object ought to occ1lpv ar. -,
so we'll known that an expert can deta,+ -
placement. II he has the proper eouiDua,+ =
was long ago discovered that there va !, Lt,.
0o"aIu one SIDE n such n body was travslnrg
away from the observer. and toward -. =,
SIDE II 1t were approaching him Furtbsrr,o-.
the amount Of the displacement indicates tb -
at which the object travels. Work OF This rs,.
class has been one OF the specialtiez OF +bs -,
Observatory. on Mount Hamilton In CaIIf,-T5,
anu .le auaIlty OF the apparatus there has mads
possible computations beautifully precise
AT Mount Hamilton. however II fg -.o--4t,-
scrutnizs only part of the heavens sourb - ~.
celestial equator. In order to supplement he g.
sdlions gong on at the main observatory.
therefore. the director Professor " u C,r,1,a-,
naturally wished 10 send Observers and i1e+r-,r-.
20 convenient point IN South Auarfes r4f- -
sire was realized last year, Through the kind7as.
or an Eastern friend OF the institution IN n
NILS. he was enabled to send an expedition % ,s
city OF Santiago. in Chilli " H. Wright 81 -
observatory star, was placed In charge ~ ~.
work The efhquipment consisted p-fucluaI1, A. .
rejecting telescope Ca cOncavs mirror OF u7arvs,,
peFtection). about three feet In diameter and
spectroSc0pe placed IN its focus Photoeranbt,
plates were then adjusted in such a n,annsr y, !,
register the images OF the stellar specrra for ,rn
seqUent examination. The latter branch - e.
work. as viii readily be seen. could be confuctss
with the utmost deHberaron az anv sl5saorsr-
time. record OF this kind. too is perraDs,4
from bulletin recently issued from the Lick
Observatory it is learned that betweeen septsmbe-
II. 1903. and June / 1904. Nr. Wright secured an
successful "spectrograuls.''
Only few OF the deductions u1a6a from, M,
ma lef1al already secured mentioned in tbs
bulletins. Six stars are mentioned Wh0sa vs1os5
ties show singular irregularitv Or, 80 t tg4oel-
speed OF only Il kilometres secondZwss rra S
probation placed upon that behavior Is tSar 1Ss
al "hose spectrum vas photographed has an in
lag about a point lying somewhere between t5ST
a NUMBER OF stars are now known whose double
spectra would be obtained simultaneously al timsS
one side and those OF tho other IN the o6Soss
direction II thus appeared that one member 81
the other toward him When thev bsS trsvsIIs5
so far in their orbits that thew r6vsJ s, O- ~
line OF sight then the Shifting az fbs lines ~ ~
two sDectra ceased temporarily. Stars eThfbitinF
that sort Of phenomena are called "spectroscoDis
binaries-S The name would to apply like
wise 70 those bodies which; Ike The few mentioned
s se 'eeT TJ9rT Sy 29 s s2seEgm Say 7 vas
IKE a single star. revealed the fact thar Il Is
Mr. Wright. has examined with special cara
AIpaa Ceh54lrl WIIcn IS 1ar down IN the southern
heavens This object has a peculiar interest Tor
from It takes oDIV sbot P6r % realS 10 trasrss "a
Interval which separates II from the earth where
as the nearest star IN the Northern Hemisphere.
81 Cygni. is between six and seven light years
double. and Mr.; Wright made careful measure
ments OF the velociries Of the two members Both
are recedng from the earth at an average speed q
lItSsn t'5s q seCo-- C~.ls % men olo5ss'
fers from time to time That. OF course was TO
larty enters into the figures, however. and needs
explanation. Mr.. Wright suggests that possibly
the IS a triple. He regards that suppOsiJioR
less probable than some others which could be en-
tertained. but Es says that it cannot be over
looked.
The late Dr.. Roberts. English astronomer.
estimated that the two "compOnents' Of thts in
teresting double were almost equal In size TIA
proportion between the two being 81 to 40. Mr..
Wright thinks that a revision OF this opinion may
be necessary when the star has been studied fur
Their SpecJT0sCOpiCaUy- Very often the differences
between companions is much greater-s2y Ike thar
between the earth and the noon which at
short distance would look like binary system
Another fact ascertained by the Santiago eNpedi-
tou is that IN temperature and composition the
larger component Of Alpha Ceutaurt belongs IN the
same class with orr sun. All stars suns. but
there is a great diversity in their spectra- M
Wright says THAT at least halt of this one belongs
to the solar type
00n IN Cn 1TlC