Evening star., 1937-12-12
new 'SUPER-NOVA'
DISCOVERY TOLD
Was 100000 Times
Brighter Than Sum-" Scien-
tist Claims.
BY THOMAS r. HENRY.


hibit of the Carnegie Institution of
Washington yesterday by DR.. Walter
s. Adams, director of the Mount Will
son Observatory.
Every now and then, DIR. Adams ex-
planned, star explodes. The sun
might blow up some day but nobody
on earth would know anything about
1t because everybody would be ''vapor-
lied" the instant it happened and 60
floating into space as puffs of gas. For
that matter nobody need worry about
1t. At the upper limit there may be
100 such explosions year in this star
system. There are approximately 1O0,-
600 100000 stars averaging about the
size Of the sun, so the catastrophe
which would make gas Of everything
IN the solar system as far out as the
upper layers Of the earth is not likely
to happen more than once in billion
years.
The explosion observed by DR.. Fritz
Zw;cky of the Mount Wilson staff
happened in another star system g.
Oo0,00 years ago It was noted for
the first time on September Slight
travelling at approximately 100000
miles second having required that
much time to reach the earth. The
light OF this one star suddenly fared
up until it exceeded the light of all the
other stars in the island universe of
which it was a part.
Star Brighter Than Sun.
A few months before in another
island universe, DR.. Adams said, such
an explosion had been observed in
which the star became approximately
100000 900 times as bright as the sun.
This was the greatest super-nova on
record, but it was observed just before
1t disappeared in the west. so very few
observations could be taken. The new
super-nova apparently was caught on
the Photographic plates at about the
time when it reached its climax.
Previous observations both in the
Milky Way star system of which the
sum is part and in other galaxies
show that these explosions, in which
the light of star increased a Million
fold or more, last only a short time
after which the celestial body returns
TO normal, An immense amount of
its material, however, is blown out
and afterwards may be collected in
titanic ring around it.
1t takes more sugar to make pound
In Upper Marlboro than in Rockville.
A gravity survey of $50 square miles
surrounding Washington, in which OBJ
servations accurate to one part in a
million were made at 10 places, is the
subject OF another exhibit. This was
made possible during the last few
months by new gravity measuring
device by which the pull of gravity
can be determined in few minutes.
Inc instrument was invented by DR..
F. E. Wright of the Geophysical
Laboratory.
How Weight Is Determined.
The weight" of an object, DR.
Wrlghs explained. is the resultant of
two forces acting upon it-one of
which is pulling it to the earth and
the other the centrifugal force due
TO the planets rotation which is try-
Ing to throw it off the earth. There
is constant tug of war between these
Two. The centrifugal force is con-
slant for any particular latitude. Con-
sequently If the gravity pull differs at
two places the weight of the same
object differs.
There is fairly constant decline
the local survey shows, between Rock
vile and Upper Marlboro. But no.
body need worry about it, for the diff
ference in weight is far too minute
70 be detected by any commercial
weighing device. Very minute differ
ences In gravity, and hence in weight.
were found in three observations made
IN little over mile along River road
IL is quite different, DR.. Wright ex-
planned, when widely separated noints
on the earth's surface are involved.
He oold the story of a prospector who
carried 200 ounces of gold from North
ern canada to Peru. When he got
mere his gold weighed only 1879 ounces
Inc same situation was encountered
more than $50 years ago by the French
astronomer, Jean Richer, who found
that pendulum clock, accurately
regulated in Paris, lost 215 minutes a
oay IN the Cayenne colony of North
ern South America. The time of the
SWING OF the pendulum depended on
tne resultant between the two con-
nlctlng forces, which differed marked
~ between France and South America
Wnen you go up to the tenth floor in
an elevator you weigh trifle less than
you did on the ground floor. An avi-
ator hy1ng at $4,000 feet, DR.. Wright
explained. weighs approximately half
a pound less.
Gravity Surveying Slow.
Inc best method of measuring pray-
1ty, DR.. Wright said, still is by ex.
Temely accurate timing of the swing
OF pendulum, but each observation
requires considerable time and labor
This makes gravity surveying a slow
!oo and only few observations can
be taken in a given area. It is i'm
possible to learn the fine deviations
between stations. Previously. for ex-
ample. knowledge of gravity around
washington had depended on two OBJ
servations by the pendulum method.
one at Rockville and the other at Up-
per Marlboro.
With the new instrument rapid and
extremely accurate observations can
pe made every half mile or less. As
many as Is can be completed in a
Gay. Deviations in gravity are of
great Importance, DR.. Wright ex-
planned. in deducing the underlying
Seoioglcal structure. Thus the differ
ence between Rockville and Upper
marlboro is due, in large part, to the
oinerence in the depth of sand and
other light material everything the
heavy, basic rock.