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UA'S OLDEST TELESCOPE HAS BEEN UPDATED FOR 21ST CENTURY ASTRONOMY
From Lori Stiles, UA News Services, 520-621-1877
April 22, 2003

The University of Arizona's oldest telescope officially turns 80
tomorrow.

But far from being a museum piece, the 36-inch telescope now has a
new mosaic of four charge-coupled device (CCD) electronic imaging
detectors and a new mirror that make it more useful than ever in the
modern era search for Near-Earth Objects, or NEOs.

Formerly sited on the UA campus in Tucson, the telescope was moved to
Kitt Peak in 1962. In 1969, astronomers used it in making the first
detection of an optical counterpart of a pulsar, a star that
regularly emits short, intense bursts of radio waves or X-rays.

By 1982, Steward Observatory no longer used the telescope, so Steward
Observatory Director Peter Strittmatter granted exclusive access to
the telescope to Spacewatch astronomers, directed by Tom Gehrels of
the Lunar and Planetary Laboratory (LPL), on the condition that they
refurbish and maintain the instrument.

"The Spacewatch team rose to the challenge," said the LPL's Robert
McMillan, who now directs Spacewatch.
-------------------------------------
Contact Information
Robert McMillan
520-621-6968  bob{at}lpl.arizona.edu
Tom Gehrels
520-621-6970  tgehrels{at}lpl.arizona.edu
---------------------------------------
Spacewatch members developed an electronic imaging detector system
and made the first trial scans with a small CCD in May 1983. They
developed and pioneered the technique of scanning the sky with a CCD
on this telescope, which they have been using in their survey for
asteroids and comets since 1984.

Last October, the Spacewatch team converted the telescope, installing
a new mosaic of CCDs and installing a new primary mirror. More on the
story, and pictures, are online at the Spacewatch website,
http://spacewatch.lpl.arizona.edu/09meter.html .

"The new mosaic of four CCDs covers nine times more sky area than the
previous detector, giving us faster coverage of the sky in the search
for NEOs," McMillan said. "So far, we have discovered six NEOs in 25
nights of full time observing, and detected many others that were
previously known." 

Coincidentally, Spacewatch used the original 80-year-old mirror until
April 23 last year, when they decommissioned the telescope for the
upgrade. The original mirror, and the original parts, are carefully
stored in the telescope building, "so that in the distant future,
antiquarians could in principle restore the telescope to its 1923
configuration," McMillan said. 

Steward Observatory and its first telescope were created with
tenacity, daring, ingenuity, and prodigious hard work.

Andrew Ellicott Douglass, who came from Harvard College Observatory
to join the Lowell Observatory at Flagstaff in 1894, immediately
mounted a campaign to establish a major astronomical observatory in
southern Arizona when he joined the University of Arizona faculty in
1906. 

Many influential Arizonans at that time considered astronomy a
luxury, when university students needed facilities for more practical
education in mining or agriculture, for example.

Douglass, famous also for establishing tree-ring science, or
dendrochronology, spent his first decade at UA trying to raise funds
for the university observatory.

The UA's first telescope was financed by a private benefactor. She
was Mrs. Lavinia Steward, a resident of Oracle, Ariz., and an amateur
astronomer. In 1916, a year before her own death, she anonymously
donated $60,000 to the observatory in honor of her late husband.

The early history of the telescope is described in George E. Webb's
book, "Tree Rings and Telescopes," (University of Arizona Press,
1983). 

Douglass telegraphed his order for the telescope body and mount to
the engineering firm, Warner and Swasey, of Cleveland, Ohio, in early
February 1917. The agreement was for the university to pay $33,600 in
quarterly payments, with the firm insuring the instrument until
delivery. As it turned out, Waner and Swasey were too busy filling
$2 million in wartime military contracts to begin work on the
telescope project until 1919, completing it in 1922.

Unable to order a mirror blank from France during World War I,
Douglass ordered it from Brashear Company in Pittsburgh, with the
understanding that the glass would be manufactured within five
months. Brashear gave the contract to the Nation Optical Glass Co.
The firm's attempt at casting a 37-inch mirror blank was removed from
the annealing oven badly cracked. 

By mid-April 1919, Bashear arranged for the Spencer Lens Co. of
Buffalo, NY, to cast the 37-inch disk, which Brashear would optically
finish, at a total cost of $6,000. No American glass company,
including the Spencer Lens Company, had ever attempted to make such a
large glass telescope mirror blank. Glass disks for such telescope
mirrors had typically been made in France -- by a factory that had
been destroyed during the war. 

By December 1919, Douglass was totally frustrated with the Steward
Observatory.

In 1920, things began to turn around.

Douglass hired Godfrey Sykes, then living in Tucson, who had built
much of the Lowell Observatory at Flagstaff, to design the Steward
dome. He hired local Tucson firms to build the campus observatory at
a reasonable cost. By this time, Warner and Swasey were making
serious progress on the telescope body and mount.

The Spencer Lens Company made its first attempt at casting the glass
disk. That mirror, cast in December 1920, cracked in annealing. (Who
then could have dreamed that today, only a lifespan later, Steward
Observatory's own world-famous Mirror Lab would cast and polish
exquisite telescope mirrors up to 331 inches across in a giant,
spinning furnace?) 

A power failure ruined Spencer's second casting attempt, in July
1921. A third mirror, cast in mid-August 1921, also cracked in
annealing. But on Dec. 22, 1921, the firm telegraphed Douglass that
it had successfully produced and annealed the Steward Observatory
mirror. The glass was shipped to Brashear in Pittsburgh in January
1922, where workers had to remove 3 inches from the diameter and 2
inches in thickness before it could be polished and finished. The
mirror was silvered and shipped to Tucson in July.

Douglass finally was able to put it all together, and on July 17,
1922, brought the crescent Venus into focus.

The university launched its new observatory with a formal dedication
April 23, 1923. Then-UA President Cloyd Heck Marvin addressed an
audience of several hundred people at the observatory, which was east
of other buildings then on the UA campus.

The guest register was signed by Calvin Coolidge, then vice president
of the United States, among other notables, McMillan said. "We still
have that book with those signatures," he added.

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