The Portland daily press., 1896-01-04
STAR HUNTING BY CAMERA.
Photographic Work of Harvard AS
Economical Stations.

Photographic Work of Harvard AS
Economical Stations.
Stars Invisible to the Largest Telescope
Caught on Sensitive PIates-Discovery
Economical Needs and Possibilities.
Particular attention has again been
drawn to the work of the Harvard as
Economical observatory both by the dis
eovery of Nova Carinea, a new star in the
consolation of Carina, and by the ship
ment of the magnificent Bruce photo
graphic telescope to the astronomical
station at Arequipa. During the last
1000 years, from the beginning of the
record by the famous astronomer Hip
parohus, the discoverer of the first So
called new star, B. G. 1874, down to the
present day, only fifteen Of this descyip-
tion have been not ed. an average of less
than one in century. 1t is q triumph,
therefore, for Harvard observatory to have
made the latest addition to this notable
list, and, more even than this, to have
won this credit twice in succession. Be-
fore the coming into view of Nova Car
inca, the last in line WAS Nova Normae,
also the discoverylof the Harvard observa-
tory, made exactly two years earlier
These stars, technically new, are not
permanent additions to the heavenly host.
They come into being or into sight only
to glow with intensify1ng radiance for a
few weeks or months and then to fade
away by dissolution into gaseous nebulae.
The special interest attaching to these
transitory beacons of the sky is In the
material which they afford to students
for instructive analysis and comparison
and the light which they cast on the
formation of the universe and its laws.
For the extension of this scientific in
vestigation the Harvard observatory is
today preeminently fitted. 1t is by no
peculiar or unearned favor of fortune that
this conservatory is today in the forefront
of discover y. but simply because of it's
unequalled completeness of equipment in
astronomical stations, appliances, and
observers. Its stations at Cambridge,
Mass, and at Are quipa, in Peru, on the
slope Of the Andes, afford complete field
OF view of the heavens surrounding both
the Northern and Southern heInispheres.
This comprehensive range of survey Is
necessarily beyond the reach of any single
station, no matter how advantageously
situated or superbly equipped for obser-
vaticn. 1t has also at Arequipa the larg-
est refraoting telescope in use on the
Southern hemisphere, at point where
the steadiness and clearness of the atmos-
phere are exceptionally favorable for as
Economical work. This instrument a
thirteen inch Boyden telescope, is not of
large size compared with the thirty-six
inch Lick refractor or with many others
north of the equator, but it's observations
are of great comparative value in view of
the fact that there are SO few telescopes of
even moderate power in the station south
of the equator.
The Harvard observatory has the dis
tinguished honor of having been the first
to undertake stellar photography and of
having carried the undertaking to proper
lions beyond any suggestion of rivalry.
The first Photographic image Of star
was taken at the Cambridge observatory
by Prof G F. Bond and ]. A. Whipple
on July II, 1850. A daguerreotvpe plate
was used and only the brightest stars left
permanent image. A few years later
the work was resumed with the use of the
oolodion process and glass plates, and
many excellent photographs were thus
obtained. In 1879 DR.. Henry Draper was
first to succeed in making photograph
showing the lines in the spectrum of a
star, and with the aid of more sensitive
plates and other improved appliances the
observatory during the last ten years has
made great progress in the art and in It's
collection of plates.
In photographing the stars set of lenses
for the purpose takes the place
OF the object glass in the telescope, and
by the attachment of prism to the
lenses photographs of the stellar spectra
are obtained. 1t is through the photo
graphic telescope that the recent discover
les of new stars have been made, for an
of the exposed plates showed
a marked difference in the spectra which
is apparent even to an unframed eye
With the use of the most sensitive plates
the faintest stars visible to the eve
through the telescope have been photo
graphed, and, in the photographs of
nebulae aud the most distant stars, the
astonishing result has been attained of
the reproduction of stars too faint to be |
seen by the most powerful telescopes. |
The area of sky covered by the plate used |
by the Harvard observatory is 100 square
degrees, and as the total area of the sky
is about 10000 square degrees, 400 plates |
are sufficient to map the entire sky. |
Complete photographs of the heavens
havo been repeatedly made by the obser-
vatory, and individual stars and clusters