Evening star., 1931-12-09
MILKY WAYS SIZE
OVEREST|MATED,
SCIENTIST CLAIMS
Discovery of Dust and Gas
Clouds Cuts Figures
Down to Fifth.
MOUNT WILSON STUDY
UPSETS OLD THEORIES
DR.. Frederick H. Seares Bares Re-
suits Of New Calculations Here
at Carnegie Institution.
BY THOMAS r. HENRY.

Inc great Milky Way galaxy of stars.
Vi Wnlch the sun. with its planetary
system, Is part, may be only one-fifth
as pig as astronomers have believed
one OF the most far-reaching changes
IA astronomical theory in recent years.
Ieac!ieo as a result of observ aticns at
the Mount Wilson Observatory of the
Carnegie Institution of Washington was
announced here last night by DR., Pred
erlck II: Seares, assistant director of the
observatory. ''-e
Inc galaxy Is pictured in current as
tronomy as vast aggregation of some
Wnere between 10000, 900 900 and 40 =
ooo,00O,000 stars, spread through SPACE
N a lens like form and thickeSt in the
region of the Milky Way. This celestial
lens mas been estimated to be about
Lou,OO0 light years In diameter, or the
oastance that light, moving at about
aoo'ooo miles second, would travel in
IVo,oo0 years. The sun is one of these
stars, ABOUT medium in six and tenn
perature, but possibly unique in the
system in having satellites esnecia Iiv
OF the sort capable of supporting life
as IL Is known on earth,
Star Clouds Noticed.
ontl few years ago this galaxy was
consioered to constitute all of creation
Inen came the startling discovery. also
at the Mount Wilson Observatory that
ann OBJECTS in the distant heavens were
.ioe parts OF the galactic system, but
themselves great star clouds, located At
q AM MINIMUM OF approximately a million
sns years beyond the borders of the
socaueo MILKY Way universe" The
. s.le creation as 1t existed for the
nao OF man was increased many thou
SANG times by this discovery.
Ine so-called spiral nebulaep wer.
Lhoependent galaxies, Of the same sort
Us tne Milky Way galaxy itself. II was
SHOWN tnat II somebody could get far ont
III space, say, million light wears uay
and LOOK at our own system IL wo,,ld bs
spiral nebula. Distance of ons ~
tnese distant "univefses" hayinp haen
eeStaoiished, it was possible to estimafe
sne uStance OF all the others bv their
prlgncness. From this it was possibia
W estimate the size, The curious thing
NS was tiaat tne biggest OF them was only
uuous one-nftn the size Of the Milkv
,as as saidA5. Mans destiny seemed TO
nave oeen cast in the great metronnlis
OF the heavens, compared with whscb
ene others were only large towns. This
III unnamed tne astronomical picture until
II. sears announcement last NIGHT
~ astronomers apparently must berfn
toholng up their measuring sticks SO far
as tner own universe" Is CONCERNED
IL mas appeared to them much birosr
enan II really Is because they have been
On Inc inside looking out, instead of IN
the outside looking in.
Ane new observations, according tn
-. ". SeareS announcement, make IL nrar.
11aCany certain that the Milky WAY pa
10y 10y considerably smaller than as
Eo..' Eeis naVe calculated In the past.
now much reduction win be nacassary,
mas not been determined. but IL NAV -.
snae Wnen the calculations are carries
o. Uas iuiy the galaxy will shrink to the
spiral nebulate. s"iaesic
The. currently accepted estimate :,
sne size of the gelactic svstan, ~. W
oeaLes pointed out, depends on the cai.
tuiate1 distances of globular star Gins
& sels. Ihese are nearly spherical COM
paeG aggregatlons, consisting of thou
IaIas Is. OF stars. They belong to the pa
raS: put are systems within a system
ponSiuy resty comparable to neighborhood
ino ns Si.An city. There are about
an ~ ~ snem IN the Milky Way galaxy
W,.hy ssy extend to Its farthest limits.
are lne peculiar type Of stars known !. ?
Sepho Variables, which flare IN anS
slow oim at regular intervals. when
sne period OF one of these Intervals i.
nuown, astronomers. by applying =
ttnatnematical formula, can deterr,irs
:. ;.e actual brightness of the star This
Is then compared with the annarane
prlentness. The difference bv an,In-
ing anotner astronomical formula csn
Ne translated into terms of distanca
me dlmmer a star appears in corr
paItson TO its known brightness the
lsrtner away it is. VIC
Clouds Dim BriIIiancy.
;, But this method of measuring t,.
diameter OF the heavens assumes that
we only factor reducing the briehtnsss
OF the star is distance. Now II in~~r
mas neen known that there are oraa4
SlouGs on dust and gas scattered over
Iie Mlky way, but astronomers havs
IrStnlsseo S.Ss them as local phenonennn
nnen tney could not be detected there
mas Deem no disposition to assume their
Studies Of the galactic system ,how
that It's form is very similar to one ~
lhe spiral nebulae. One of these "lini-
ssS Uses can De looked at from the out
sae ana seen as whole. The sir-
alilcant lt feature in the spirais. said Dr
oeares; Is the wide distribution over the
.s .itiaI pane OF dark, obscuring clouds
s.niitaI 10 tnose known to exist in the
s eaaaotic system. In the spirals, how
dense that, when one of the great star
systems is seen edge-on, they form an
opaque band running from end To end
OF the lens-shaped image. The GER
slai structural similarity of the spirals
ano our own system justifies the in
ference, the Carnegie Institutior as-
tronomer said, that the ohscur;ne,
CLOUDS OF the galactic system are IiEae
wise widespread over the central nIan.
NOW. ne explained, there is great
Ine IN the Milky Way, between the
CONSERVATION Cygnus and Circinus. If
- Ae great river OF light that sepa-
ian iaes hto TWO strea.ns. Astronomers
t1s tp1 nave speculated on the nature Of
s rns. recent photographs, made
Ross Of the Yerkes Observatory r-
Seares said, show conclusivelv that - :.
formed by dense absorption Clouds Tn
other words, the rift is what the orao,Is
pano running through the spiral nebula
looks IKE when observed from the in
siue OF the system. The globular cllIs-
cefs' rne landmarks for determination
oi ceiestial dimensions, have been OBJ
served through great clouds of star
ouSt. This made them look DINNER.
and consequently far more distant,
than they really are.
Tne work upon which DR.. Seares' an
nouncement last night was based win
oe among the exhibits open to the pub
nc at the Carnegie Administration
Building. Sixteenth and p streets, sat-
urday. Sunday and Monday following
the annual meeting OF the trustees on
Friday There will also be exhibits
the gx14ctic system