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Inauguration of Arecibo Observatory Upgrade

[In case you're wondering how this relates to meteorites, the radar telescope
 at Arecibo is used to bounce radar off of objects in the solar system.
 In particular, radar have been bounced off of asteroids and comets
 that make close passes by Earth.  A good example of this is when 
 asteroid 4179 Toutatis made close flybys in 1992 & 1996:

 http://newproducts.jpl.nasa.gov/calendar/toutatis.html

 Ron Baalke
]

Cornell University

Inauguration of the upgrade to Arecibo Observatory is June 14
World's largest radio telescope is even more powerful, sensitive

FOR RELEASE: June 12, 1997

Contact: Larry Bernard
Office: (607) 255-3651
E-Mail: lb12@cornell.edu

ARECIBO, Puerto Rico -- A five-year, $27 million upgrade to the world's most
sensitive radio/radar telescope at Arecibo Observatory will be dedicated on
Saturday, June 14, with Neal Lane, director of the National Science
Foundation; Pedro Rossell, governor of Puerto Rico; Carlos Romero Barcel,
resident commissioner to Puerto Rico in the U.S. Congress, and Hunter
Rawlings, Cornell University president, helping inaugurate a new era of
radio astronomy.

The telescope, the world's largest single antenna radio telescope (305
meter, or 1,000 foot) and the world's most powerful radar, is poised for
scientists to get detailed information about exotic objects in the distant
universe, detailed surveys of comets and objects within the solar system and
new information about Earth's upper atmosphere.

The upgrade, begun in 1992, features a new system for focusing radio signals
using a system of Gregorian reflectors; a new, more powerful 1 million-watt
radar transmitter; and a 50-foot-high steel mesh ground screen to reduce
ground interference. The facility, operated by Cornell University's National
Astronomy and Ionosphere Center (NAIC) under cooperative agreement with the
NSF, was upgraded with funds from the NSF and NASA.

"We at NSF are delighted at the prospect of U.S. scientists being able to
capitalize on the existence of this extraordinary new facility to make
dramatic improvements in our understanding of many parts of the universe in
which we live," said Hugh Van Horn, director of the Division of Astronomical
Sciences of the NSF.

In addition to Lane, Rossell, Barcel, Rawlings and Van Horn, scheduled to
speak at the dedication ceremony, to begin at 11 a.m. at the observatory,
are:

Daniel R. Altschuler, director, Arecibo Observatory; Paul Goldsmith,
director, NAIC, and Cornell professor of astronomy; Hugh Van Horn, director,
Division of Astronomical Sciences, NSF; Robert Dickman, coordinator of the
radio astronomy facilities unit, NSF; Carmen Pantoja, Smithsonian
Astrophysical Observatory; Donald Campbell, associate director, NAIC and
Cornell professor of astronomy; Harold Theiss, retired chief engineer, NASA
Office of Space Communications; and Joseph Taylor, Princeton University.

Arecibo Observatory is a radio/radar telescope that uses electromagnetic
radiation, or radio waves, to study phenomena that occur as close as 3
kilometers (about 2 miles) above Earth in the upper atmosphere -- or exotic
cosmic objects many billions of light years away, at the edge of the known
universe.

The upgrade -- the second since the facility was built in 1963 -- will allow
scientists to do in one hour what previously took 10 hours. The sensitivity
will improve by a factor of about 20 for studies of the solar system and by
a factor of about three or four for studies of distant galaxies. Also, more
radio frequencies are available with increased sensitivity at all
frequencies. Astronomers will be able to "observe" signals farther away, and
thus, further back in time, than ever before. The telescope's frequency
range, and thus its sensitivity, previously 50 MHz to 3,000 MHz, now
increases to 10,000 MHz.

"Scientists are eager to use this new instrument for a variety of studies,"
said Paul Goldsmith. "We will look at how galaxies form and how stars are
born, at fainter pulsars, other worlds' moons, and the dynamics of the upper
atmosphere with more bandwidth, more clarity, better resolution and greater
sensitivity than ever before."

The upgrade had been under planning, design and construction since the early
1980s. Over that time, many people, both within NAIC and Cornell and from
other institutions in the United States and overseas, have been involved.

"It has been a tremendous group effort over a long time to bring the
original idea of the Gregorian reflector system to the reality that you see
today," said Donald Campbell.

Unchanged in the upgrade is Arecibo's trademark reflector dish. The
305-meter (1,000-foot) dish is unlike any other. Most radio telescopes use a
parabolic antenna that can be steered to any direction. The Arecibo antenna
is spherical and remains fixed -- but the focusing device suspended above
the dish can be steered. Thus, signals can be captured from a greater slice
of the sky.

A radio/radar telescope captures and transmits radiation at radio
wavelengths, unlike optical telescopes, which capture lightwaves. So clouds,
haze, even daylight do not interfere with radio astronomy. The big dish --
the primary reflector -- is the world's largest single dish radio antenna.
It captures these electromagnetic waves and reflects them to a secondary
reflector enclosed in the dome suspended above it, which in turn
concentrates them to a focal point. After being amplified, the signals are
sent via fiber optic cables to the operations building, where further
processing and data recording occur.

The improvements help all of Arecibo's areas of study. The three main areas
of Arecibo's attention are in atmospheric science, solar system studies and
studies of our galaxy and the universe. In extragalactic studies,
astronomers studying the large-scale structure of the universe have a much
improved ability to measure velocities and masses of galaxies, which in turn
could yield clues to the "missing matter" of the universe.

In solar system studies, comets and near-Earth asteroids can be studied in
far greater detail with the upgraded radar system. Beyond the solar system,
an increasing number of pulsars become accessible, and with the increased
sensitivity, new planets, if there, may be found. And Arecibo is well-suited
to study the chemistry of star formation. New stars form out of cold clouds
of dust and gas, which emit no visible radiation, but the molecular material
emits radiation at radio wavelengths in the coldest regions of the galaxy.

In atmospheric studies, the dynamics of the upper atmosphere can be studied
in greater detail. Studies of the ionosphere, the region of the Earth's
atmosphere above 30 miles (50 km), which consists of ions -- atoms that have
lost one or more electrons as a result of solar ultraviolet radiation -- are
important for understanding the chemistry of the upper atmosphere, including
auroras, thunderstorms, lightning, space debris and meteorites.


[Image, http://www.news.cornell.edu/science/June97/Arecibomain.lb.html]

The 1,000-foot reflector dish of the Arecibo radio/radar telescope
rests in a mountaintop sinkhole in Arecibo, Puerto Rico, set 450
feet beneath the structure supporting the dome, which houses a system of
reflectors used to focus radio waves picked up by the telescope's dish. It
is the world's largest single-dish radio telescope and most powerful
radar. Photo by David Parker, 1997/Science Photo Library

[Image, http://www.news.cornell.edu/science/June97/Arecibomain.lb.html]

The Fundacion Angel Ramos Visitor and Educational Facility is
nestled on a hilltop overlooking the 1,000-foot reflector dish at
Arecibo Observatory, Puerto Rico. The center has exhibits, an auditorium,
meeting rooms, office space and an observation platform with a breathtaking
view of the radio telescope. Suspended 450 feet above the reflector dish, at
left, is the structure supporting the dome, which houses a system of
reflectors used to focus radio waves picked up by the telescope's 1,000-foot
dish. Photo by David Parker, 1997/Science Photo Library

Arecibo Facts

* BEGINNINGS. Arecibo Observatory was built in 1963 by the U.S. Air Force
under the initiative of Professor William Gordon in the Department of
Electrical Engineering and his colleagues at Cornell University. It was
primarily intended for radar studies of the Earth's ionosphere, but it
was realized that the telescope would be a very significant new
instrument for the then relatively new fields of radio and radar
astronomy. In addition to its astronomical observations, it is still
used for atmospheric and ionospheric studies. It has been managed by
Cornell University since its construction, first for the Air Force and,
after 1970, for the National Science Foundation.

* FIRST UPGRADE. The original 1,000-foot-diameter fixed spherical
reflector had a wire mesh surface that limited its operation to radio
frequencies below 600 MHz (50 cm wavelength). Shortly after the
observatory was made one of the NSF's National Astronomy and Ionosphere
Centers in the early 1970s, this surface was replaced by 38,788 very
accurately shaped aluminum panels, which allowed the telescope to
operate at much higher frequencies with the highest about 3 GHz (10 cm
wavelength). At the same time, a high-powered transmitter (420
kilowatts) was installed for planetary radar studies. This upgrade was
financed by the NSF and NASA.

* SECOND UPGRADE. Begun in 1992 and completed in 1997, this upgrade
replaced the line feeds with a Gregorian reflector system as the main
method of focusing radio waves reflected from the 1,000-foot dish. The
Gregorian reflector system will allow the telescope to operate over the
full frequency range allowed by the accuracy of the 38,788 panels of
the primary reflector, up to 10 GHz. Also included in this upgrade are
a 50-foot-high, steel wire mesh ground screen around the perimeter of
the 1,000-foot dish, which shields the telescope's receiving system
from radio noise radiated from the surrounding ground, and a new 1
megawatt transmitter for planetary studies. This upgrade also was
funded by the NSF and NASA with a contribution from Cornell University.

* THE DISH and SCREEN. The reflector dish is 1,000 feet in diameter (305
meters) with a depth of 161 feet (51 meters) , as big as 26 football
fields, covering 18 acres. Its surface is made of 38,788 reflective
aluminum panels, each 3-by-6 feet. The ground screen is 50 feet high
surrounding the perimeter of the primary antenna, the reflector dish.
This screen has an area of about 16,000 square meters, the size of five
football fields. The screen reduces radio noise emitted by the ground
that gets into the receiver systems.

* THE NEW MIRRORS. The Gregorian reflectors are suspended 450 feet (137
meters) above the primary reflector dish. The suspended mirrors, and
associated sensitive receiver systems and new radar transmitter, are
housed in a six-story, 90-ton, 86-foot diameter enclosure. One
reflector is 72 feet in diameter, the other, 26 feet. The whole
structure is attached to trolleys that move along the 304-foot-long
curved feed arm suspended above the dish.

* FREQUENCIES and RANGE. The system operates at frequencies between 50
MHz and 10,000 MHz (10 GHz), with wavelengths between 6 meters and 3
centimeters. Its range is as close as 4 miles (6 kilometers) above the
Earth to several billion light years away, at the edge of the known
universe. It is sensitive enough to eavesdrop on a cellular phone
conversation at the distance of Venus.

* RADAR. The 1997 upgrade includes a doubling of the power of the
transmitter, to 1 million watts from about 420,000 watts, used for
radar studies of the solar system. The new transmitter combined with
the telescope forms the world's most powerful radar system. This can
result in images of remarkable resolution: about 1/2 mile (1 km) for
the surface of Venus, down to 50 feet (15 meters) for asteroids and
comets. That is sensitive enough to detect a steel golf ball at the
distance of the moon.

Arecibo Accomplishments

Here are just some of the accomplishments scientists have made using the
Arecibo Observatory:

* The first planets outside the solar system were discovered around a
pulsar (early 1990s). Pulsar B1257+12 is a rapidly rotating pulsar with
three Earth-like planets in orbit.

* One of its first accomplishments: Establishing the rotation rate of
Mercury, which turned out to be 59 days rather than the previously
estimated 88 days (1965).

* Detailed maps of the distribution of galaxies in the universe (late
1980s).

* The first pulsar in a binary system was discovered (1974), leading to
important confirmation of Einstein's theory of general relativity and a
Nobel Prize (1993) for Russell Hulse and Joseph Taylor of Princeton
University.

* Investigation of ice in craters at the polar regions of the planet
Mercury with the radar system (1990s) and, recently, similar
investigation of the lunar poles for evidence of ice (1997).

* Provided much of our pre-Magellan mission knowledge of the surface of
Venus via 1.5 km (1 mile) resolution imagery of the surface through the
planet's cloud cover using the radar system.

* The observatory has made major contributions to our understanding of
the chemistry and dynamics of the Earth's upper atmosphere and
ionosphere.

* Discovery of two classes of pulsars: millisecond pulsars, which rotate
several hundred times per second, and slower-rotating pulsars, which
rotate about once per second. The slow-rotating puslars speed through
space, while millisecond pulsars move slowly through space.

* Arecibo Observatory is uniquely suited to search for signals from
extraterrestrial life, by focusing on thousands of star systems in the
1,000 MHz to 3,000 MHz range. No such signals have been found.

* Arecibo Observatory provides a unique setting for Hollywood filmmakers.
The observatory was the setting for the climactic scenes in the James
Bond movie Goldeneye, and a good portion of the movie Contact, based on
a novel by Carl Sagan and starring Jodie Foster, takes place at
Arecibo. That movie is scheduled for release July 11, 1997.