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Office of Public Affairs
Williams College
Williamstown, Massachusetts
Media contact:
Jim Kolesar,
Dir. of public affairs, Williams College
jkolesar @ williams.edu
March 29, 2006
Scientists, Residents, and Tourists Marvel at Total Eclipse of the Sun
KASTELLORIZO, Greece -- Scientists from around the world joined this
Greek island's 250 residents and countless visitors Wednesday in
cheering the drama of the Moon totally blocking the Sun, revealing the
dancing glow of its corona.
"It was even more fabulous than we expected," said Jay Pasachoff,
professor of astronomy at Williams College (in Williamstown, Mass.) who
observed his 42nd solar eclipse. "All the technical equipment worked
perfectly, the corona shone brightly, and the activity around sunspots
on the eastern edge of the Sun provided an even more dramatic show than
predicted."
Chair of the International Astronomical Union's Working Group on
Eclipses, Pasachoff led an expedition of dozens of scientists and
students to record images from the rare, three-minute event. They are
capturing data over many eclipses to understand better why the Sun's
corona, the outer halo of million-degree gas, shines hotter than the Sun
itself. Most of the corona is visible from Earth only for the fleeting
time that the Moon totally blocks the Sun's direct rays.
Tourists and residents, who had packed the tiny island's harbor-side,
cheered at the appearance of the "diamond ring" effect that brought the
total eclipse to a close while ships blew their horns in celebration.
Two of the group's experiments involved taking rapid series of images,
ten times per second, with new electronic cameras through specially
designed filters. One filter passes a narrowly defined color in the
green portion of the light spectrum and the other passes a narrowly
defined color in the red.
Each is emitted by gas in the corona from iron that has been heated to
such high temperatures that it has been stripped of 13 or 9 electrons,
respectively, from its normal 26.
A third experiment used a filter that provides an even more narrowly
defined coronal color. Known as a Fabry-Perot, it was designed and built
by the Johns Hopkins University Applied Physics Laboratory for David
Rust, a solar astronomer there. Rust and his colleague Matthew Noble
were in Kastellorizo. Williams alumnus Rob Wittenmyer '98, now a
graduate student in astronomy at the University of Texas, assisted them.
A fourth experiment involved a specially built telescope that matches a
defunct one aboard the Solar and Heliospheric Observatory (SOHO), a
satellite built and operated by the European Space Agency and NASA.
Bernhard Fleck, SOHO project scientist, was on Kastellorizo with the
Williams team.
The group also captured a further variety of digital and film images.
They included work by several veterans of previous Williams eclipse
expeditions, including Lee Hawkins from Appalachian State University in
North Carolina and Jonathan Kern of the Large Binocular Observatory in
Tucson, Ariz. Kern made images with a camera and filter modified to
flatten the extensive dynamic range of the corona to enable the delicate
coronal structure to show on a single piece of photographic film.
Also collaborating was John Seiradakis of the Aristotle University of
Thessaloniki and two of his students. They were joined by Margarita
Metaxa of Athens, who works with Pasachoff on the International
Astronomical Union's Commission on Education and Development, and two of
her students.
The Williams contingent included Bryce Babcock, coordinator of science
facilities and staff physicist, and Steven Souza, instructor in
astronomy and observatory supervisor, along with six students: Megan
Bruck '07 of Tempe, Ariz., Paul Hess '08 of Simsbury, Conn., Shelby
Kimmel '08 of Newton, Mass., Jesse Levitt '08 of Natick, Mass., Amy
Steele '08 of Orlando, Fla., and Anna Tsykalova '08 of Ardmore, Pa. Also
assisting was the expedition's medical officer, amateur astronomer Paul
Rosenthal, M.D., of Williamstown.
For the current expedition, Williams College received a grant from the
National Science Foundation, to support the faculty, students, liaison
with Greek colleagues and various equipment and shipping expenses.
Pasachoff also received an earlier grant from the Committee for Research
and Exploration of the National Geographic Society. The new electronic
cameras were supplied by an equipment grant to Williams and MIT from the
Planetary Sciences Division of NASA. They could be used because the
eclipse cameras and Pluto cameras have similar specifications.
Additional support was provided by the scientific honor society Sigma
Xi, the Massachusetts Space Grant, the Rob Spring Fund, and the Ryan
Patrick Gaishin Fund. Some of the photographic equipment was lent by the
National Geographic Society and by Nikon.
Wednesday's eclipse began at dawn on the eastern tip of Brazil and raced
across the Atlantic Ocean and eastern and northern Africa before passing
over this easternmost point of Europe. From here it swept across Turkey
before ending at dusk in Mongolia.
Though brief (the longest lasted seven minutes) total eclipses draw
astronomers and thrill-seekers from great distances, in this case
multiplying the population of this tiny island -- filling every hotel
room and camping on the town's soccer field.
The next total eclipse of the Sun occurs in 2008 over a narrow path from
northernmost Canada, over Greenland and Russia, to central China.
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