History of the Landolt Astronomical Observatory
Dedication, March 30, 2006
The presentation of the keys-to-the-observatory to Dr. Landolt were
made by Chancellor Sean O'Keefe and Professor Joel Tohline.
The observatory on top of Nicholson Hall was first opened in
1939. The telescope is a refracting telescope with the lens having a diameter
of 11.5-inches. The maker of the lens and the telescope was Alvan Clark & Sons.
Clark was the premier maker of refracting telescopes and indeed is universally
acknowledged to be the world's all time best maker of refractor telescopes.
LSU is lucky and proud to have such a classy instrument.
Long-focus refractors give a high-quality high-magnification
view that is perfect for looking at the Moon and planets. Wonderful amounts
of detail can be seen on the planets, including Mars' volcanoes and polar
caps and morning-fogs as well Jupiter's Great Red Spot and fine divisions
in Saturn's rings. For the Moon, we can see large and small craters, huge
impact basins and low volcanic domes, with the views being wonderful and
makes one think of flying low over the surface of the Moon. The 11.5" Clark
telescope is also good for looking at double stars and bright nebulae around
From the late 1940's to the 1970's, the telescope was used
for taking many astronomical photographs for various purposes including scientific
studies. However, for scientific purposes, the telescope can no longer compete,
as its aperture is too small and the light pollution from the city makes
for a very bright sky.
From 1939 to the early 1990's, the telescope was used for
regular Public Nights as well as LSU classes of many types. Many people around
Baton Rouge fondly remember coming out to see the wonderful sights with this
excellent scope. The growing light pollution has little impact on visual
views of the Moon and planets, as these are intrinsically bright targets.
In the early 1990's, the observatory fell into disuse and
some disrepair. The causes are just the normal ones that primary users retired
and moved away, while its scientific utility was lost. From the mid-1990's
until 2005, the observatory was essentially unused with the dome getting
in poor shape. But the Clark telescope and lens don't 'decay', so in 2005
a group in the Physics and Astronomy Department worked long hours repairing
and refurbishing the telescope. Most of this was in scraping and repainting
everything, polishing the brass tube, replacing the doors and windows, and
making a variety of repairs. The Clark lens was untouched. So finally, in
early November 2005, the Department had a Grand Reopening with a Public
Night at the time of Mars' closest approach. After almost two decades
of inactivity, the Clark telescope is again showing beautiful views of the
sky to students and Baton Rouge residents.
At the time of the Grand Reopening, it was realized that the
observatory did not have a name. The obvious name for the observatory was
to honor Professor
Arlo U. Landolt for long being the core of the astronomy program at
LSU. With his long years of serving as the Secretary of the American Astronomical
Society, Dr. Landolt is the most recognizable of American astronomers.
And his long work at providing standard stars (used for calibrating photometry
as is vital for ~10% of modern astronomy) is by far the most-sited paper
in all astronomy. Given his long and very strong contributions to LSU astronomy,
American astronomy, and world astronomy; it is appropriate to dedicate
the observatory as the "Landolt
Astronomical Observatory" as a small recognition of his work.