 The
first day of the convention started with a welcome from
Louisville Astronomical Society Convention Co-chair
Sally Lambert. She welcomed everyone to the convention
and filled us in on some of the activities. Next came
Evansville Astronomical Society Convention Co-chair
Mitch Lumen who also welcomed us on behalf of the E.A.S.
Finally, Astronomical League President Barry Beaman
welcomed everyone and reported that the Astronomical
League was growing rapidly and expanding in many other
ways.
The first speaker was Chuck Allen
of the Louisville A. S. who spoke on "Our Mister H-Bomb",
a takeoff on the Bell Labs' movie "Our Mr. Sun" from
the 1950s. Mr. Allen compared the way the Sun makes
energy and a H-bomb make energy. The Sun and the H-bomb
both make energy by nuclear fusion; the combination
of lighter atomic nuclei to form heavier atomic nuclei.
In the process, a small amount of the Strong Force that
holds the nucleus together is released as energy. This
occurs because more of the Strong Force is needed to
hold together the protons and neutrons in two separate
atoms than the same number of protons and neutrons in
a single atom. When atomic fusion occurs, the excess
Strong Force (which appears as additional mass in the
original nuclei) is converted to energy and radiated
away from the atom. While the process is the same, the
way it is achieved in the H-bomb and Sun are completely
different.
Nuclear fusion in the Sun occurs in
the Sun's core. Here the weight of all the matter being
pulled inward by the Sun's own gravity creates the temperatures
and pressures required to convert gaseous hydrogen into
gaseous helium (actually, both are plasmas). The process
actually progresses somewhat slowly, taking some ten
million years to burn 12% of the Sun's mass. At that
point, the Sun has finished its life on the main sequence
and becomes a red giant star.
 The
hydrogen bomb uses lithium hydroxide as its fuel. This
substance will readily absorb any water with which it
comes into contact. H-bomb fuel has absorbed water whose
hydrogen has already absorbed a neutron in addition
to normal proton. This "heavy" form of hydrogen is called
deuterium and the resulting water is often called "heavy
water". The H-bomb explosion occurs in roughly one hundred-thousandth
of a second, as compared to the Sun's 10 million years.
Approximately 40% of the H-bomb fuel is burned in the
process, the rest is blasted away before it can be burned.
The area where the H-bomb "really
shines" is in the temperature. H-bomb temperatures typically
reach between 70 and 125 million degrees, while the
core of the Sun is only 25 million degrees. These temperatures
are contained by a 3-1/2-inch steel case in the H-bomb
and by gravity in the Sun.
But the final winner in the comparison
must be the Sun, for while the H-bomb can put out between
one and 50 megatons of TNT in a single explosion, the
Sun puts out the equivalent of xxx megatons per second,
second after second for well over 10 million years.
 The
next talk was by Tucson amateur astronomer Dr. Tim Hunter
who spoke on "Tri-Color CCD Imaging at the Grasslands
Observatory". Dr. Hunter talked about the travails of
taking CCD images with an Apogee AP-7 camera using different
color filters and merging them into a single color image.
This process requires careful work to make sure that
each image is carefully guided, or instead of a beautiful
color image, you can end up with three mono-color images
blurred together, or worse, completely separate images.
He also talked about the problems of taking the correct
exposure through each color filter so the final image
would have the correct color balance.
 After lunch, Dr. John Kielkopf spoke on the construction and
use of a "Wide Field Spectral Imaging Camera". This
camera instead of taking a normal picture, would take
a "slice" of the sky with a slit aperture. The light
then passes through a diffraction grating and is captured
on a CCD. This allows Dr. Kielkopf to study the spectra
of a line along a large section of the sky. This is
especially useful for studying extended objects such
as nebulae and more interestingly comets.
Dr. Kielkopf showed some of the resulting
images. He then showed graphs displaying the spectrum
of some common objects, including Comet Hale-Bopp. In
the process of doing this, they recorded the morning
twilight, and happened to just catch the first illumination
of the sodium layer high in the atmosphere. This is
the layer that is used to create artificial stars for
image correcting systems. The camera is built with commercially
available parts that amateurs can readily obtain and
Dr. Kielkopf urged amateurs to consider doing these
kind of spectral observations.
The final speaker of the day was Professor
Warren Stephenson, who spoke on "Elemental Stability
and Nucleosythesis".
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