The Sauk Centre herald. (Sauk Centre, Stearns County, Minn.) 1886-current, 1929-01-10
new TELESCOPE
MOST POWERFUL
Half Billion Stars Will Be
Seen for the First
Time.

WaShlngtOn.-AD0ut half-Dlll10n
stars that cannot now be seen or
photographed with any telescOpei
as we'll as thousands of inconceivi
ably remote nebulae, will be withi
in the reach of astronomers when
the new 2O0-inch telescope, ani
nounced by the California Institute
of Technology at Pasadena, is COM
pleted. But astronomers are not
interested merely in great numbers,
and that alone would not justify
the millions of dollars that will be-
spent on the great instrument.
The closer and brighter things
that will be seen better are what
particularly interest the astronOi
mer. But even some of these
would have been thought impossi1
bly, far only few years ago. For
instance, there are the spiral neb-I
ulae. Thousands of these have
been observed in the sky, all with
the characteristic spiral structure
more or less evident. For years
their nature was subject of disputed
until DR.. Edwin P. Hubble of thel
Mount Wilson observatory, with
photographs made with the 100
inch telescope, still the wOrld'sI
largest, definitely showed what they
are. His photographs revealed the
individual stars of which they arel
constituted. They showed that
these nebulae are systems of starSl
like that of which the Milky Way,|
and all the stars that we can see,l
including the sun, are part.
Two NebuIae Observed.
Two spiral nebulae, out of theI
thousands that are shown, do mott
form a very large proportion, al
though there is plenty of evidenced
that the two studied are ratherl
typical of the group. Astronomers
have been anxious to observe the
two even better.
The 2OO-inch telescope will dol
this. Perhaps a half dozen or sol
nebulae, that now appear as con-
tinuous areas of light, will be re-
solved into their constituent stars.i
If this is done, their distance can
be measured.
Some distant spiral nebulae, now
invisible, undoubtedly will come
into view. The farthest now in|
reach of the 100-inch telescope are;
something like $40 million million|
million miles away-so far that
their light takes 14O-million years.
to reach us. With the new tele-I
scope thousands beyond will bel
visible, the farthest of them be-
ing nearly five thousand million)
million million, or five sextillion|
miles from us. And when they are
seen, the light exposing the photo
graphic plates will have been on|
its way for a thousand million|
years-since a time long before
man appeared on the earth, and
when the planet itself was still
young.
Sun Will Be Observed.
Another field for the 2OO-inch|
telescope will be the members of
the solar system. AS it is planned
to make the mirror of quartz, which,
will not expand distortingly under|
the suns rays, it will be possible
to use it for observations Of the
sun. The planets will be brought
almost to within hailing distance,
and some of the present-day mys-
teries concerning Mars, Jupiter and
the other planets may be solved.
In deciding on a telescope with
a mirror 200 inches in diameter,
the astronomers are making the
greatest jump in size since Isaac
Newton invented the rejecting
telescope. It was in 1872 that, I'M
order to overcome the defects that
were then inherent in refracting
telescopes, in which the light rays
were brought to a focus by glass
lens, he made the first reflector.
Here, a dish-shaped mirror reflect
ed the rays back toward the object,
and at the same time brought them
to a focus. A second, and fiat,
mirror, reflected the rays to the
side, where the observer could see
the image, without getting his head
in the way. NewtOn's original re-
fiector, with a mirror only two
inches in diameter, is still in the
possession of the Royal society I'M
London. In 1928 the astronomer,
Hadley, showed the proper curves
that should be given to the mirror
to give the best images, and from
then on large reflectors became
possible.