East Oregonian : E.O. (Pendleton, OR) 1888-current, 1907-11-22

ture but one millimeter (O.O3y lnch)
in diameter. After such a plate was
developed, it could of course be en-
larged by an ordinary camera, ana
bigger Maritan picture obtained.
For minute study of planetary de-
tail this method would lead to re-
suits of no practical importance.
It may be asked, Why not use
telephoto lens on Mars? This has
led to splendid results in landscape
work, giving a picture of mountains
Is to 20 miles distant as If they
were only a short way off. This is
in reality the very process used in
photographing Mars or Jupiter. A
magnifying lens is placed in the tele-
scope just before the Photographic
plate, and an enlarged image of the
planet is obtained. Prof Todd has
used a magnification of about five
diameters in getting his Andes photo
graphs. A greater enlargement than
this is practically impossible.
The much heralded photographs of
Mars taken with such an expenditure
of time. energy and money (the orig
inal photographs cost about a dollar
apiece have the scant diameter of
3-16 of an inch, and the photograph
ic work must be of the very best,
and great observational difficulties
must be overcome to produce even
these tiny pictures.
Mars Near the Earth in 1907.
Mars was closer to the earth in
1907 than it has been at any time
since 1892; but unfortunately for the
observatories of America and Eu-
rope, it was very low down in the
sky At the beginning Of July, when
nearest the earth, Mars at the Yerkes
observatory was never more than 20
degrees above the horizon. This ne
cessitated looking through a great
thickness of the earth's atmosphere.
It was to diminish the Ill effects OF
this atmosphere that the Lowell ex-
pedition went to the top of the Andes.
Prof Barnard, with his beautiful
photographs of the Milky-way and
star clusters, has shown more than
bil!ties Of photography in astronomi-
cal work. With the 40-inch Yerkes
telescope, he made splendid photo
graphs Of Jupiter. At the focus Of
this great telescope lover so feet In
length) Jupiter when nearest the
earth appears directly as an image
3-16 inch in diameter. When en-
larged five diameters Jupiter is near
ly an inch in diameter, just as II 1t
had been photographed with tele-
scope 900 feet in length!
But Jupiter is more easily photo
graphed than Mars; first, because In
the telescope it is about twice as big
as the ruddy planet; and second, be-
cause Jupiter's surface being about
two and a half times brighter than
that Of Mars, shorter exposure is
necessary. To get original negatives
Of the same size from the two plan
cts. it would be necessary to give
Mars ten times the exposure of Jupi-
teri
The astronomical world is await
ing with great eagerness the verdict
of Mr.. Lowell when he examines
carefully the Andes photographs. II
nothing definite is proven this year
regarding the canals Of Mars, there
will be another chance to try 1t
again in 1909. Then the planet will
be even closer than 1t was this sum-
mer, but what is more important, 1t
will be rs degrees higher in the sky,
and this will permit the Lick and
Yerkes telescopes to turn their full
power on Mars, and make photo
graphs which with the latter instru-
ment will be as large as one-half
inch In diameter.