The New York herald., 1922-07-02
Continued from First Page.

ira were photographed as frequently
as possible and the positions of the
doubled lines were seen to be contin-
ually changing. Sometimes, the
stronger lines We're displaced to the
red and the weaker TO the violet end
o. the spectrum and sometimes the
opposite was the case. The former
irdicated that the brighter star was
receding, the fainter approaching us
and vice versa.
Further spectra showed that the
brighter star was revolving at
speed of 12S miles and the fainter
took nearly fourteen and half days
to make a complete revolution around
each other. A comparatively simple
calculation then shows that the two
bodies must be at distance of about
100000 miles apart, three-fifths the
distance from the earth TO the sun and
slightly less than the distance of We
nus from the Sun. If the two stars
combined were of the same mass as
Venus and the Sun they should revolve
in about the same period, 225 days,
but as a matter of fact, they revolve
ir fourteen days, one-fifteenth of the
time and at speed over seven times
as great as Venus. This evidently in
dicates very much stronger gravi-
rational pull between the two bodies
and very much greater mass.
If we know the period of revolution
and the separation of two bodies in
space, two suns, or a sun and planet,
OF planet and satellite, we can easily
calculate the mass of the two by a
comparatively simple relation derived
from the law of gravitation called the
Harmonic Law. This law states that
the combined mass of the revolving
system is proportional to the cube of
the separation divided by the square
of the period. In all these calculations
we use the Earth Sun system as the
standard and as the Earth has only
one three hundred and thirty thou
sandths the mass of the Sun, 1t can be
neglected and we get the mass of the
required system in terms of the Suns
mass.
Hence in this case we have the dou-
BILE star revolving in a period of 14.4
divided by 365.25. about one-twenty-
fifth of the Earth's period, the year,
at distance of 55.000,000 divided by
| $4,000, 900, or about three-fifths the
Suns distance. From the Harmonic
Law then the mass of this double star
will be three -fifths cubed, divided by
one-twenty- fifth squared the mass Of
| the Sun, which comes out 1875 times
the Suns mass. If we use the exact
fractions we find that this system has
| 1889 times the mass of the Sun. that
| the brighter star is 1876 and the
fainter 63.3 times the SUMS mass, or
about four times greater than for any
previously discovered system.
! A further calculation from the spec
II oscopic observations shows that the
two bodies are revolving in an ellipse
around one another of nearly the
same shape as the orbits Of the plan
| cts. But the spectroscopic results
cannot tell us anything of the inclina-
ton of the planet of this ellipse to the
line of sight. If this plane passes
through the earth, the distance and
masses are as given above, but IL not,
they must be greater than calculated.
From considerations Of the probable
I
tances apart, 1t is practically certain
that this plane is inclined more than
fifteen degrees, else the two bodies
would mutually eclipse each revolution
| and there would be n decrease in the
! line which has not been observed
This condition makes it probable the
combined mass is 100 times the Sun.
while If we consider all inclinations
equally likely the probable average
value would be 220 times the Suns
| mass.
May Revise Stellar Theories.
The very great mass of these two
bodies shows that they must be ex-
! ceptional in many respects and this
discovery may require some revision of
the theories of the formation and con-
stitution of the stars. However that
may be, we can easily deduce further
interesting data about these two tre-
mendous stars. L have already said
that they are about forty times as
bright as the Sun for each unit of area
and as they are so much more massive
they must be much bigger.
Two methods are available for de-
termining how much brighter they
ere than the Sun. The first is wholly
theoretical, developed by Prof. Edding-
ton of Cambridge, from which we find
that the brighter star is about 20,
and the fainter $4,000 times as bright
as the Sun.
However. there is some uncertainty
about these values and we can use
another method depending uDon tha