Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-05-19
ASTRONOMER ASKS
AMATEURS HELP
FOR CONTEMPORARY
Georgetown Director Urges
Scientists to Search for
Light Clouds.
REV. PAUL A. McNALLY
CONVINCED THEY EXIST
Sir Isaac Roberts Denies Existence
of Mysterious Objects
in Sky.
BY THOMAS r. HENRY.


For the sake of an old man, who
has spent lifetime studying the glories
Of the heavens and who is approaching
the end of his work, bitter at the
thought that observations he is sure
are correct are questioned by his CO.
temporarieS, Rev. Paul A. McNally,
director of the Georgetown University
observatory yesterday appealed to anna
teur astronomers to search the skies for
certain distant, faint, mysterious clouds
of light.
Father McNally himself is convinced
that they exist and that he has seen
some of them. He wishes to make the
Georgetown observatory clearing house
Of such observations in an effort to
clear up one of the most disputed points
in astronomy.
Speaking before the American Asso-
citation Of Fixed Star Observers at the
National Academy of Sciences Building
yesterday. Father McNally explained
that in 1911 Sir William Herschel, most
celebrated of all observers Of the sky,
listed So of these mysterious objects
and gave their exact positions in the
heavens. Apparently nobody else saw
them at the time. and the dispute did
not arise until a half century later,
when the British astronomer, Sir Isaac
Roberts, tried to check on Herschel.
He found only eight of the So and
denied the existence of the others. THIS
caused Edward Barnard of the Lick
Observatory, whose star charts have re-
Gently been published by the Carnegie
Institution of Washington, to come to
the defense Of Herschel on the grounds
that such a great astronomer couldn't
have gone so far wrong.
Sought Vainly for Evidence.
Barnard, however, had tried to get
evidence in vain by photographing the
heavens. He kept quiet about the mega
tive results of his plates, but Father
McNally examined them last Summer
and found that they showed nothing.
The next person to take up tne Wo[k
was Father Hagen, former director OF
the Georgetown Observatory and now
director Of the Vatican Observatory.
He entered the work. Father Mentally
said, without any bias in favor OF
Herschel, but was surprised to find the
mysterious clouds of light in almost
the exact positions where the English
man had found them century before.
After checking his observations he pup
lished them a few years ago.
Then astronomers all over the world
began disputing his findings, because
they have been unable to find the same
things. This, Father McNally said, the
old astronomer resentS and his letters
to the Georgetown observatory reveal
an increasing bitterness and BELIEF that
his lfework has ended in failure. He
has sent to Georgetown the entire col
lection of his sky maps showing the
location where he claims he saw the
nebulous areas. Meantime, the widow
of Sir Isaac Roberts has entered the
controversy, strangely enough in oppo-
sition to the position Of her husband.
She has sent Georgetown file OF his
charts for checking against those OF
Father Hagen in the belief that the
cause Of the difference will be found.
There seems little doubt, Father NC
Nally said, that such areas exist although
they can be detected through the tele-
scope on very clear nights after the
observer has been In the dark Tor
time. Although the camera can detect
objects in the heavens far too faint for
the human eye, these patches cannot
be photographed for some unknown
reason. Every sort of device has been
tried for photographing them but the
resulting plates show no result. Father
Hagen himself has failed repeatedly
and even. Prof Hubbell of the Carnegie
institution, discoverer of the island
universes, has been unable to get any
record.
Urged to Search skies.
Father Mentally urged that persons
with telescopes take advantage Of clear
nights to search the skies by the
GEORGETOWN charts. There are various
dark areas in the sky, he said, which
seem to be of the same nature but
more intense. These also d1Ey the
camera. Some have held that they are
great masses Of dust or meteoric ma
terial which shut off the light from the
stars in some areas. These can be
found quite easily. But although they
seem dark when viewed through a
high powered glass, they seem lighter
than the surrounding sky. BY first
concentrating on these, he pointed out,
it will be easier to detect the less in
tense Herschel areas. These are quite
extensive and fade out gradually into
the clear sky.
The great swarms of meteors offer
exceptional opportunities to amateur
observers, said Prof. Charles P. Oliver,
who urged that any seen while taking
variable stars observations be recorded.
From those visible to the naked eye, he
said, there is very rapid increase as
fainter and fainter magnitudes are OBJ
served through the telescope until they
begin to fall off just as rapidly as they
have risen. There is no way to deter
is further away from the earth or
smaller than the brighter objects I'M
less actual paralax measurements are
made, such as those formerly used to
determine the distances of the nearer
stars. 1t Is especially important, he
insisted, to get better picture of those
in the immediate neighborhood Of the
earth.
The fate of So-called novae, or new
stars, after they have declined in bright
ness was discussed by DR.. w. H.
Stevenson, former president Of the
British Astronomical Society. These
are stars Of which two or three appear
in a century, mount in a few days to
the brilliancy of the planets, so that
they are the brightest objects In the
sky, and then fade out Of sight. This
phenomenon is supposed to be due to
stellar collisions or explosions which
happen centuries before the light which
tells the story reaches the earth.
Tho more recent novae, Prof. Steaven-
Photographic plates taken before their
appearance as very faint stars. He has
compared them after their great de-
cline1 end find that they 60 back about
where they started from. From then on
tiny Ecrd'y change at all.
TIE were papers by B. p. Garasi-
movie of Harvard University on an OBJ
scure type Of variable stars. and by Dr.
a.. w Brown on the progress of the
occuitation campaign.
Yesterday afternoon the astronomers
visited the Georgetown University OBJ
servatory and the Bureau Of Standards.
The convention ended last night with a
banquet etatepp4 Press Cub -,