Evening star., 1934-12-11
SCIENTISTS PROBE
NEW SPACE LIMITS
NebuIa 1880, 900, 600, ,o0o,-
900, 900, 900 Miles Away
Studied by Institution.
BY THOMAS r. HENRY.


Penetration to new frontier
Of space, 1880, 900 ,000, ,000, 900 ,0O0, 900
miles away is announced by astrono-
mers of the Carnegie Institution of
Washington as one of the outstanding
accomplishments of the years work
to be reported at the annual meeting
OF the trustees here December IL.
This utmost extent of physical OBJ
servation of the content of creation
Is represented by the discovery of a
very faint nebula in the constellation
of Bootes in the northern heavens,
near the great star Arcturus.
The distance is approximated from
the speed, as shown by the spectro-
scope, with which this object is mov-
ing outward from the observer. 1t
appears to be moving at rate OF
about 80 500 kilometers a second. ap-
proximately one-Sixth of the speed OF
light itself. This is the Swiftest mo-
tion yet observed for a heavenly OBJ
ject and, since the speed of outward
motion is directly proportional to the
distance by formula worked out by
the Carnegie Institution astronomers,
it indicates the most distant object.
Billions of Stars in Galaxy.
The Bootes nebula is presumably
galaxy of several billions of separate
stars, roughly approximate to the
whole Milky Way galaxy, of which
the sun is a part and which includes
all the stars visible in the heavens
with an ordinary telescope. This new
island universe" as the spiral nebu-
lac are known, may even be much
larger. Little can be determined about
1t because of the immense distance.
The distance is so vast that the
light which made its faint impression
on the plates at the Mount Wilson
Observatory must have started from
the Bootes nebula approximately 200
million years ago, about the time when
the great dinosaurs were beginning to
appear on earth and the vast swamps
which became the coal beds Of today
were f1ourishing.
The reason for the increasing out
ward speed of the distant nebulae still
Is matter of considerable discussion
among astronomers and is one of the
chief reasons advanced for the hypo-
thesis of an expanding universe lit
orally creating space and time as its
borders push outward.
Much Work Completed.
Much observational work has been
done on the island universeS during
the year, according to the report being
prepared for the Carnegie Institution
trustees, with the result that they now
are believed to be much larger than
was the case few years ago when 1t
was first determined that they were
enormous star galaxies.
At that time they were believed to
be considerably smaller, on the aver
age, than the Milky Way system. But,
the Carengie astronomers report, the
disparity in size between the stellar
system and the spiral nebulae in An
dromeda, one of the easiest to observe
and study, was much reduced by TAX
ing account of the obScuring clouds of
dust and gas scattered along the
Milky Way. This made necessary a
reduction in the earlier estimates of
the size of our own star system, and
the reduction has been confirmed by
recent measurements made by the
Mount Wilson astronomers Of the COLI
ors Of the globular clusters, immedi-
ately outside the Milky Way galaxy.
Seen through dust clouds they are
redder than normal by an amount
which increases with the density of
the clouds, thus indicating a loss of
blue light similar to that affecting
sunlight when the sun is near the
horizon. The faintness of the clusters
and of all objects seen through the
clouds is thus seen to be caused partly
by the clouds themselves instead of
distance.
Observations Corrected.
On the other hand, observations of
the Andromeda nebula with more SEN
sitive instruments reveal traces of
luminosity far beyond what was first
shown and roughly double the dimen-
sions to approximate parity with those
of the Milky Way system. The di-
ameterS of both now appear to be
approximately 100000 ,0O0, ,00O, ,OOO, 900
miles. Light, moving at 10000 miles
a second, requires about 100000 years
to go from one end to the other of
either star system.
After the meeting of the trustees, to
whom reports of the years work will
be made, the exhibits illustrating the
progress in various lines will be open
to the public December IS, 16 and II,
with daily lectures by the Mount Will
son astronomers and others.