Evening star., 1940-12-17
Of Stars, Men
And Atoms
Notebook of Science PROGRESS
In Laboratory. Field
And Study
By Thomas r. Henry.

By Thomas r. Henry.
Our solar system is member OF
compact little family of 81 stars within
a radius of about $4,000, 100000 miles, 1t
was reported today by astronomers Of
the Carnegie Institution OF Washington.
The number is increased with the dis
covery by DR.. Adrian Van Maanen of
the Carnegie Mount Wilson Observatory
of two hitherto unknown stars within
this range which, with allowances made
for distance, each produce only about a
ten -thousandth of the light and heat of
the sun. They are, nevertheless, actual
stars, shining with their own light rather
than with reflected light-as does the
moon or any of the planets.
They evidently represent a state to
which the sun is approaching as it grows
smaller at rate of billions of tons a
second by dissipating its substance into
it will be several billion more years be-
fore the parent star of the earth be-
comes such glowing cinder in the in
fnity of space.
The finding of such objects, which
hardly could be detected at greater dis
tances, is leading to radical revisions of
estimates of the number of stars in the
Milky Way galaxy, the vast star system
Of the visible heavens Of which the sun
is part. The number has been esti-
mated as more than 50,000,000. It is
now considered probably much larger
because there is no reason to suppose
that such objects as those found by DR..
Van Maanen should be confined to the
suns neighborhood.
In spite of the vast distances between
them, the 81 stars, and perhaps others
yet to be discovered, constitute some
sort of knot in the stream of the galaxy.
The nearest of all is the star Alpha
Centauri, visible in the southern heay-
ems, which is so far away that its light,
moving at 10000 miles a second, re-
quires about five years to reach the
earth
Thirteen stars in the group are dou-
these is Alpha Centauri itself. A double"
consists of two stars constantly revolv-
Ing around each other. Whether anv
Of the 81 have planetary systems like the
sun is unknown, but it is extremely doubt
full There would be no means of de-
tectlng even an object the size of Jupiter
shining by reflected light at a distance
Of light year
The vast spaces between the stars of
this sun family are not entirely empty,
1t is shown by another study by DR..
Theodore Dunham, jr., of the Carnegie
staff, but are filled by a strange sort of
gas so tenuous that there are only about
two infinitesimably minute particles of
it in million cubic feet.
This gas consists Of ionized calcium
atoms of this element stripped of one or
more OF their electrons by the ultra
violet radiation from stars shining
through them. This discovery came
from the detection of faint lines due to
calcium in the light of one star about
1855 light years away from the sun and
just outside the local region of space.
This line, 1t could be determined. was
not due to the light emitted by the star
itself, but to the luminosity it created by
stripping the calcium atoms with which
1t came In contact over its long path
But when DR.. Dunham made the same
sort OF measurement on another star
about 200 light years away and in a
different direction, he found that the
calcium line in the spectrum was much
1alnter. This shows that, however tenu-
GUS it may be, the calcium gas gathers in
clouds in space Measurements of very
the Milky Way have shown that there
are even thicker calcium clouds in the
very distant reaches of space.
While it has been known for the past
decade that there are gas and dust
clouds in what had been considered
empty space, which redden the light
from distant stars and completely hide
the center Of the universe, the Carnegie
astronomers found for the first time this
year that there are clouds of molecules.
Two OF these chemical combinations
IN the depths of space have been identi-
fed from their spectrum lines. One Is
hydrocarbon gas composed of one atom
OF carbon and one atom of hydrogen.
The other is cyanogen, the simplest pos
sible combination of carbon and the
heavy gas nitrogen, which is the principle
constituent of the earths atmosphere
There are several other types of chemi-
cal gasses, the astronomers report, which
they have been unable to identify as vet
because OF the extreme faintness of the
spectrum lines When identified, they
believe, all these will turn out to be
simple gasses, well known on earth.
They have also identified sodium, CAL
cium, potassium and titanium in the
space dust clouds, all in uncombined
forms.
Argues for Purchase