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Saturday, the last day of the convention,
started with a talk read by Derald Nye of the International
Occultation Timing Association (IOTA). The talk, "Timing
Occultations of Bright Stars with Camcorders" by David
Dunham, president of IOTA, describes how to use a camcorder
to observe and time an occultation. These occultations
can be either total occultations or grazing occultations.
The main ingredient was a star bright enough to be recorded
by the camcorder with the bright lunar limb nearby.
It is not as hard as it sounds. It is helpful to record
WWV time signals on the audio track while taping the
occultation.
Dr. Richard W. Schmude, Jr., Chemistry
and Astronomy Instructor, Gordon College, Barnesville,
GA., talked on "The Seasonal and Diurnal Variations
of Sporadic Meteors". Dr. Schmude had been studying
the observed rates of sporadic meteors by four different
observers and applied statistical techniques to these
observations to study their variations.
Diurnal variations are fairly well
known. After sunset, each succeeding hour almost linearly
until sunrise. Hence the best time to look for meteors
is just before dawn when the observer is standing almost
in line with the direction of the Earth's motion around
the Sun. The seasonal variations are somewhat more complex,
but at least in the northern hemisphere, the later half
of the year has many more sporadics than the first half
of the year. Whether these are from old, uncataloged,
meteor streams, or from other causes is not known. Nor
is it known if the same pattern holds throughout the
year in the souther hemisphere. More observations are
desperately needed.
 The
final talk was by Dr. John Bally, University of Colorado,
Boulder, on "Jets, Outflows, and Proto-Planetary Discs".
Using images obtained from the Hubble Space Telescope
(HST), Dr. Bally described the wide range of phenomena
that has been observed from the Hubble. HST, with its
above-the-atmosphere imaging, gives us high resolution
views of objects that are badly blurred from ground-based
telescopes.
Gas clouds condensing into new solar
systems are the source of many of the phenomena in this
talk's title. As its gravitational field pulls the parts
of a cloud tighter together, the cloud begins to spin
up just as a skater does when they bring in their outstretched
arms. The gas above and below the plane of spin falls
into the plane forming a proto-planetary disc. The gas
and dust in the plane orbit the central condensation
of the cloud, kept from falling toward the center by
its angular momentum. Eventually, some of this dust
and gas will form into planets circling the star-to-be.
During the last stages of star formation,
material from the inner regions is squirted outward
along the spin axis of the central condensation. These
linear features, called jets, extend for many billions
of miles from the central condensation out into interstellar
space where we can observe them. First seen by radio
astronomers, the HST has allowed us to see these jets
in visible light.
As the central condensation gets hotter,
it begins to fuse hydrogen into helium, transforming
it into a star. As the energy from the fusion process
leaves the new star, it pushes the remaining dust and
gas out of the inner solar system, sweeping it clean.
Dust and gas remain in the outer regions of the new
solar system merging gradually into the remains of the
original gas cloud.
In a star forming region such as the
Orion Nebula, the outflows from the older young stars
tear dust and gas from the outer regions of the gas
clouds forming new stars. The HST has allowed us to
see these tiny teardrop shaped clouds. At the heart
of each of these teardrops is a new sun that we can
barely see. The remaining dust blocks much of the light
from getting out of the new solar system, and what does
get out comes from the red end of the spectrum for the
same reason we get red sunsets. So the final image starts
with a bright background of dust and gas. Against that
is a black teardrop shaped cloud with the new star appearing
as a red dot in its middle. The tip of the tear drop
is pointing away from an older, nearby star whose outflow
dominates that region of space.
Space is full of many interesting
and beautiful examples of "Jets, Outflows, and Proto-Planetary
Discs". Dr. Bally showed many examples of each one from
many regions of the sky.
Saturday afternoon was a free period
for attendees to go out and enjoy the local tourist
attractions. But as the sun sunk behind the mountains,
the final event, the Awards Banquet dinner convened.
The meal provided an opportunity for friends to dine
together for the last time at the Fiftieth Anniversary
Convention. The talk at the tables was friendly and
full of astronomical gleanings.
 After
the dinner, special awards were presented to the early
organizers of the Astronomical League, Ed Halbach and
Charles A. Federer. No Astronomical League Award was
presented this year. Dennis di Cicco was presented the
Leslie Peltier Award for observing excellence. Finally,
the National Young Astronomer Award was given to Ms.
Heather Cameron for her work on solar observing. She
received a 10-inch Meade LX-200 presented by Mr. Sheldon
Fawarski of Meade Telescopes, and a lifetime observing
pass to McDonald observatory in Texas.
The after-dinner speech was given
by Leif Robinson, Editor-in-Chief, Sky and Telescope
magazine reporting that "The Golden Age of Amateur Astronomy
is Now". Mr. Robinson explained that even though many
amateur astronomers feel that the days before the ever-present
streetlights were the heyday for amateur, today's advanced
technology put the amateur astronomer on the same plane
as the professional astronomer.
One example that Mr. Robinson cited
was Dennis DeCicco, who, from his backyard in Boston,
had discovered over 100 minor planets using a sixteen-inch
telescope and a CCD camera. The technology of the CCD
camera allows the light pollution to be removed in the
camera and faint objects to be observed. While film
records both the object and the light pollution, the
CCD camera can be set to remove the light pollution
from the image. This leaves just the object and the
noise, and after taking a number of exposures of the
same field, they can be added together to average out
the noise and leave only the object. This allows those
who must work in a light-polluted environment to contribute
to the science of astronomy.
 Leif
also related a meeting of the American Astronomical
Association that brought together professional and amateur
astronomers. This meeting is the first of many that
will build a bridge between the professional and the
amateur, allowing amateurs to begin gathering data for
professionals to analyze. The American Association of
Variable Star Observers, the Association of Lunar and
Planetary Observers, and the International Occultation
Timing Association have been doing this for years, but
with shrinking budgets and the closing of the many small-aperture
observatories, amateurs could really start to contribute.
There are many areas where professionals
are unable to take the necessary data, but the amateur
can. These include long-term variable star observing,
minor planet discovery, comet and minor planet astrometry,
and long-term binary star observing. The professional
is constrained to perform observations that will quickly
result in a paper in the professional journals. The
amateur has the luxury of taking observations over a
long period of time, and on a regular basis.
Telescope time is doled out by peer
committees based on the importance of the observation,
and with the number of telescopes being reduced, routine
observations are being lost. With modern computer-controlled
telescopes, CCD cameras, and fast PCs, the amateur is
equipped to make the very observations that the professional
cannot. Amateurs must answer the call to take-up where
the professional can no longer carry on: our Golden
Age IS now.
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