Skyward
October 2019
Since early in
the last century, astronomers dreamed of the clear sky over California as a
place to unlock our imaginations and study the Universe. In 1917, the 100-inch Hooker telescope was
opened to the poetry of Alfred Noyes, who wrote:
We creep to power by inches. …Even
to-night
Our own old sixty has its work to do;
And now our hundred-inch: I hardly
dare
To think what this new muzzle of ours may
find.
The Seth Nicholson Dome |
The one hundred inch telescope |
And just think
what the telescope did find; among
many other things, it revealed that our Universe was double the size we thought
it was. Despite the fact that I have
visited Mount Wilson many times, my most recent visit in September gave me an
insight I hadn’t experienced before. I was a guest of Scott Roberts, whose
Explore Scientific telescope company had organized an observing party there.
The place literally oozes history through every stone, piece of wood, and gear
revealing the progress of our understanding of the Universe as it increased
during the 112 years since the observatory’s founding in 1907.
During my
visit there I felt as though I was standing next to some of these great
astronomers, now long gone. I was
standing next to George Ellery Hale as he struggled to build the Snow solar
telescope, the mighty 60-inch, and the 100-inch Hooker telescope. I was standing next to Fritz Zwicky as he
used the 100-inch on so many nights.
Zwicky had quite the reputation as a curmudgeon. He might have included me among the many
colleagues he called “spherical bastards” – meaning a bastard no matter which
angle or prism you choose to look through.
I was standing
next to Walter Baade. There is a story
that, at the outbreak of the second world war, he was declared an enemy alien
and ordered to stay near his Pasadena home.
Since he, or someone, allowed the vicinity of Pasadena to include Mount
Wilson, Baade essentially enjoyed three years of uninterrupted observing time
on the 100-inch. With Los Angeles under
occasional blackout conditions that darkened the Mount Wilson sky still
further, Baade made his crucial observations of individual variable stars in
the Andromeda Galaxy that he, and Bart Bok, later used to determine the size
and shape of our own Milky Way Galaxy.
George Ellery
Hale was unsatisfied with the size and abilities of the big 100-inch telescope,
and he longed for a much larger one. He
hired Russell Porter, the amateur astronomer who had founded the Stellafane
telescope makers meeting in 1925, to work on a 300-inch telescope. When that
was deemed impractical, a 200-inch telescope was built instead. Porter’s drawings of the 200-inch were
stupendous. Realizing that the 100 was
unable to reach the north celestial pole due to its English double yoke mount
design, he envisaged a beautiful and elegant horseshoe design so that the
200-inch could point right at the pole if needed. Even the lowly 18-inch Schmidt camera
telescope, the first telescope at Paliomar, made history as the instrument
Zwicky used to discover 100 supernovae in distant galaxies, and, near the end
of its useful life, it was the telescope used in the discovery of Comet
Shoemaker-Levy 9.
I close with a
variation of a quotation by Sir Kenneth Clark.
What defines the great observatories that look to the stars and
revolutionize our understanding of them? I don’t know. But I know them when I see them. And the observatories at Mounts Wilson and
Palomar are them.
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