Evening star., 1951-11-28
a. New White Dwurfs'
Discovered Among Stars
Systematic Search Carried
Out in Southern Heavens
By Thomos R. Henry

By Thomas R. Henry
Finding of A new white dwarfs,"
most fantastic stars in the universe, has
just been announced through the Ma
tional Academy Of Sciences here.
These are small, white-hot stars which
weigh at least ton per cubic inch.
They give out as much light and heat
as the sun, yet they are less than q
thousandth the size of the sun.
The discoveries reported by DR.. vii.
liam j. Luyten of the University Of Min
nesota resulted from systematic search
OF the southern heavens with the CO.
operation OF the Steward Observatory
In Tucson and the Cordoba Observatory
in Argentina. The search was directed
especially among stars with large proper
motions.
These white dwarfs are enormously
hot stars. so hot that the outer elec-
irons have been stripped from their
atoms and only the extremely heavy
atomic nuclei remain. These nuclei
supposedly are compressed tightly to-
gether. They constitute actually solid
matter. The greater part Of all matter
known on earth, even the heaviest, is
mostly empty space.
10000 Stars Screened.
More than 10000 stars were submitted
to screening but only A showed the
white dwarf characteristics. It is pos
sible. DR.. Luyten says, that some of these
will be thrown out on further study. De-
termination OF the approximate num-
ber and distribution Of these stars is
essential for proper understanding Of
the mechanics of the universe.
The first white dwarf was discovered
at the Mount Wilson Observatory of
the Carnegie Institution of Washington
In 1915-an extremely faint star re-
volving around Sirius, the brightest star
in the sky. Its existence had been DOS
tulated before, however, because of
mysterious pertubations in the orbit
OF Sirius which must be due to the
gravitational pull of some nearby object.
1t was not until four or five years
later that the nature Of this star was
recognized. The explanation which was
suggested was too fantastic for the as
tronomers to believe. Now the enormous
weight is universally accepted.
More than 100 white dwarfs since have
been entered on star catalogues. DR..
Luyten began systematic search Of the
entire sky in 1927. which has continued
ever since. Previously about 100 of the
stars had been identified. All are rela-
lively near the solar system, speaking in
terms Of celestial distance. It Is i'm
possible to distinguish them so many
light years away, although there prob
ably are great numbers Of them.
Corn that shines with a weird blush.
white light under appropriate circum-
stances has just been reported to the
National Academy of Sciences here.
Under ordinary light it cannot be
distinguished from ordinary corn, but
when beam Of invisible ultraviolet
light Is turned on it the ghostlike
duorescence appears.
This characteristic is passed on from
generation to generation. It first ap-
peared in single Seeding grown from
seed exposed to high energy radia-
tton Of some sort In the atom bomb tests
at Bikini. according to the report to
the academy by j. H. Teas and e. G.
Anderson of 1the California Institute Of
Technology.
1t is stronger in some of the descend
ants Of this seed than in the original
Seeding. Ordinary cornstalks when ex-
posed to ultra7violet have a dull reddish
purple appearance. Apparently the
blush 1uorescence is due to some deep
seated hereditary change in the germ
plasm due to bombardment.
Fluorescence Varies.
A field of such corn under ultraviolet
Illumination would seem like a garden
on another planet. The f1uorescence
varies somewhat from plant to plant,
both in extent and in the time or rate
OF development. It increases with age
up to about the four-leaf stage, then de-
creaseS and is seldom observed in plants
over two feet high. Usually the first
leaf shows the most intense f1uorescence.
At the time of pollen shedding anthers
in the tassel fuoresce even more bril-
liantly than the seedlings.
The immature pollen f1uoresces slight
ly, the mature not at all. Drs Teas and
Anderson attribute the phenomenon to
a profound chemical change in the
plants constitution. This is evidenced
especially by the accumulation of SUBJ
stance known as anthranilic acid, speci-
mems OF which show the same sort Of
white-blue light.
This is widespread. in minute amounts
throughout nature. It Is known in vari-
Gus bacteria and, under certain circum-
stances. accumulates in animal livers.
The fuorescence, it Is postulated in
the report, results from a single domi-
nant gene which was affected by the
radiation Of the original seed. Genetic
changes. such as would result from ex-
posure to an atom bomb blast, appar-
emily often are hidden and very deep
seated.
The breeding experiments were sup
ported by grant from the Office Of
Naval Research.