The Indianapolis times. [volume] (Indianapolis [Ind.]) 1922-1965, 1933-11-21
-Dietz on Science
KNOWLEDGE OF
UNIVERSE TOLD
WITH FIGURES
Smithsonian Tables Give
Smallest and Largest
Measurements.
BY DAVID DIETZ
Scripps- Science Editor

The dimensions OF things, from
the largest in the world to the
smallest, will be found in the eighth
edition of the Smithsonian Physical
Tables prepared for the Smithsonian
Institution by Frederick E. Fowle.
The tables constitute an invoice OF
mans knowledge of the universe,
from the tiny electronS which make
up the atoms of matter to the star
clouds and galaxies of the heavens.
Spiral nebulae are at one end Of
the scale. They have an average
mass of five billion times that of
the sun. The mass of the sun in
pounds is expressed by the figure 436
followed by twenty eight ciphers.
You can multiply it out for your
self, if you want to.
At the other end of the scale is
the tiny electron with a density of
only about ninety octillionths of a
gram. An octillionth is a trillionth
of trillionth.
Preparation of the tables necessi-
tated the employment of units of
linear measure which are unfamiliar
to the layman but necessary to the
scientists to obviate the use of such
unwieldy figures as those given
above. The smallest unit of length
used in the micro-angstrom. 1t is
ten quadrillionthS of a meter. A
meter is approximately a yard,
more exactly, 1887 inches.
Light Year Is Basis
The longest unit of linear measure
used in the tables is the parsec. A
parSec is 1888 light years. A light
year, as most readers of these
articles know, is the distance a
beam of light travels in year and
is approximately six trillion miles.
A question which the layman
might logically ask is why the parsec?
1t isn't much larger than the light
and it looks like more complicated
unit. There is a reason, however,
why astronomers find the parsec
handy.
The distance of a star is deter
mined by measuring it's apparent
shift against the background of very
distant stars as the earth goes
around its orbit. This angular
shift is known as the stars par
aIlaX. A star which is lust one
parsec from the earth will show a
parallax of one second of arc. Con-
sequently, by the use of parsecs, it is
easy to translate parallax into dis
lance.
Large Figures Used
The largest distance given in the
tables is the radius of the uni
verse. This, of course, is on the
assumption that space is curved and
the universe finite, as set forth in
ElnSteln'S work of recent years. The
radius of the universe, as given bv
DR.. Edwin P. Hubble of Mt viii
son, is 80 billion parsecs. If YOU
must know what that is in miles if
is about 900 septillion miles. that is
the figure 6 followed by twenty
three ciphers.
Another big number in the book
is the total number of electrons
ana protonS in the universe. This
ngure, calculated by Sir Arthur Ed
the famous British as
is 10 followed by seventy
eight ciphers. That's 10 million times
trllllon times a trillion times q
trllllon times a trillion times a tril-
lion.
Perhaps you would like some
figures for a change. Sir
arthur gives us some of those too
Here, for example, is one dealing
with the density of interstellar
space. 1t is now known that space
stars, strictly speaking. is
not empty. There are a few atoms
and electronS to the cubic yard.
Intense Cold Measured
The density of interstellar space.
Eddlngton tells us, is 10 septillions
II a gram per cubic centimeter. He
also tells us that the Temperature
of lnterstellar space is approximate
y three degrees above absolute zero
Absolute zero is 459 degrees below
zero Fahrenheit. 1t is the lowest
possible temperature since all mole
'ular vibration would cease at it.
The Smithsonian physical tables
lave been published at irregular in
erVals since 1896. The present edi-
IGN is the first in fourteen wears
The cosmic ray, the positron. and
he neutron, therefore, make their
irst appearance in the present edi-
ion.
Advances of the last fourteen
ears have necesSitated much revi-
ION and many additions in the ia
lies dealing with the structure and
mercy levels of the atom. The
aoles devoted to radio-activitv have
llSo required many additions.
Among the subjects covered bv
he tables are specific heats. latent
heats, spectrum wavelengths, induces
II refraction, photometric data.
magnetic properties, and so on. The
ayman won't find the tables inter
eSting reading but scientists will
ind daily use for them.