SPECIAL FOCUS: Observatories and Earthstations
A Cluster of Portals for the Naked and Aided Eye
Certain
places on the earth have a special, unearthly function: these
places are built to escape terrestrial limitations, to gaze
upward and outward, to either interact with space probes and
satellites, or to search for meaning beyond this world. In the
interest of improving our understanding of the earth/sky interface,
the Center has established a special focus area relating to
observatories and earthstations. Here are two reports on compelling
and superlative places within this constellation of remarkable
constructions.
Panorama of the site from
the viewing platform of the Mayall 4-meter telescope.
CLUI photo by Lize Mogel
"Quiet, Day Sleepers," reads a sign on the way into the observatory
grounds of Kitt Peak, giving a sense of the inversion of this
unusual place, an earthbound gallery of the sky nearly a mile
above the Sonoran desert of Arizona. Like the desert creatures
that escape the heat of day, many of the scientists here are
nocturnal, as this is the place they have come to peer into
space along the lines of the visible spectrum, a form of seeing
that is best done in the dark.
The mountaintop is an unusual sight: twenty white
domes popping out of the terrestrial surface, the largest collection
of major optical telescopes in the world. There are 22 optical
telescopes and 2 radio telescopes at Kitt Peak, utilized primarily
by graduate students and professional astronomers working through
universities. The site, officially called Kitt Peak National
Observatory, is operated by the Association of Universities
for Research in Astronomy (AURA), Inc. under a cooperative agreement
with the National Science Foundation. Also at Kitt Peak is the
National Optical Astronomy Observatory, which has a sister site
at Cerro Tololo, in Chile.
Many of the individual scopes are operated by
partnerships between universities and other organizations, creating
a confounding variety of acronyms. The WIYN (Wisconsin, Indiana,
Yale, NOAO) telescope, for example, is one of four imaging telescopes
on Kitt Peak able to directly view the cosmos through an eyepiece.
Most of the other telescopes are spectrographic, automatically
collecting light emitted by the elements which make up stars
and other celestial entities. This information feeds directly
into the datastream for analysis, and can be outputted later
as "image" if necessary.
Also at Kitt Peak are two solar telescopes, including
the dramatic-looking McMath-Pierce solar telescope (the largest
of its kind in the world), and a 25 meter radio telescope which
is part of the Very Long Baseline Array (VLBA), a series of
10 similar devices across the USA which collectively track celestial
objects. Several of the telescopes are of historical interest,
such as the Kitt Peak Vacuum Telescope, built in 1973 to support
Sky Lab.
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The McMath-Pierce solar telescope rises majestically
over the volleyball court.
CLUI photo by Lize Mogel
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Kitt Peak began as an idea as the space program
got underway in the 1950s, when parallel opportunities opened
for the field of astronomy. Astronomers petitioned for a consolidated
national observatory that would be accessible to many researchers.
6,875 foot tall Kitt Peak was chosen from among 11 other mountains
considered in Arizona, California and New Mexico, mostly because
of the perfect weather for looking skyward - little light pollution
or air turbulence, clear days, low humidity. Other optical observatories
near urban areas have been rendered less effective because of
excessive light and air pollution, such as Mount Wilson Observatory
in Los Angeles and Mount Palomar near San Diego. Except for
the frequent summer lightning storms (Kitt Peak is said to be
struck by lightning more than any other observed place in the
United States except Orlando, Florida), nighttime on Kitt Peak
is dark and clear. Ground light sources in nearby Tucson are
kept dim by law so as not to interfere with the observatory's
mission.
Kitt Peak lies within the Tohono O'odham Reservation,
which was originally created by the U.S. government in 1874,
with land added and taken away by successive administrations
over a period of 50 years. Now it is the second largest reservation
in the US, with four non-contiguous segments totalling 2.7 million
acres. When first approached by the federal government about
the site, the Tohono OÙodham refused to give up the peak they
considered sacred. The tribe eventually acquiesced, apparently
after tribal leaders were shown the proximity of the heavens
when viewed through a telescope. The land was leased to the
U.S. in perpetuity, under the important condition that the observatory
would be used for astronomy only, and not military purposes.
The telescopes on Kitt Peak are in high demand
- astronomers apply for time slots a year or more in advance,
and are occasionally disappointed by bad weather. Several of
the telescopes can be visited, and tours are given daily.
Observatories
and Earthstations: Arecibo, Puerto Rico
