[meteorite-list] University of Arizona's Oldest Telescope Has Been Updated For 21st Century Astronomy

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:10:46 2004
Message-ID: <200304222013.NAA11543_at_zagami.jpl.nasa.gov>

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, Warner 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.
Received on Tue 22 Apr 2003 04:13:28 PM PDT