November 2010

November 2010 Meeting Notes

Several business items were addressed this month, including payment of dues by all members during November, our Logo Contest winner, plans for a visit to the ACT observatory and development of an observing schedule for both public and private observing sessions through 2011. John Grismore gave a brief "Introduction to Celestial Coordinates", and Virgil Reese presented a fascinating program on Exobiology.

Business Meeting

Dues

November is dues month for BAS. During the October business meeting it was agreed that we should synchronize our dues collection to a single month each year to simplify renewal tracking and collection. By the end of the November meeting about 75% of our members had paid their dues. Those who have not yet done so are asked to please try to take care of their dues in the next week or two. We ask that members complete a membership form each year and return it with dues payment. New this year is a Member Liability Release Form which has been added to the back of the Membership Form. Members should complete and sign the release at the same time in order to participate in club activities other than the normal monthly meetings. The membership form can be downloaded from our public website at <http://sites.google.com/site/bartlesvilleastronomyclub/home/join-bas> .

Logo Contest Winner

We now have a winner for our BAS Logo Contest. Apryl Dawn Kaylor was presented with a certificate and one year of free membership to BAS, as well as a copy of the book "Totality: Eclipses of the Sun", coauthored by Ken Willcox, past president of BAS. The new logo will appear soon on our public website.

ACT Observatory Visit

Members of BAS have been invited to attend the Astronomy Club of Tulsa Member Observing Night at their observatory near Mounds, OK. Maps and directions are available on request.

Observing Schedule

Arden Strycker and Steve Plank have devoted considerable time during the past year scouting for club observing sites. We now have access to several, from an easily accessible site at Sooner Park for casual observing, to one of the darkest sites in our region at Hulah Lake, for more serious observing and imaging. Recently they have developed a schedule for club and public observing events through 2011. Arden reviewed the schedule during the meeting and discussed plans for a possible public star party near the end of the month. The tentative schedule for observing events and club meetings can be viewed on our club calendar at <https://sites.google.com/site/bartlesvilleastronomyclub/calendar>.

Oak Park Star Party

Joyce Ritchie has been in contact with Oak Park School, which would like to have BAS provide a school star party for them, similar to the two we did for Wayside School last spring. We will need to do this fairly quickly, before the weather gets too cold, so she and Arden are discussing possible dates in the next week or two. If you're interested in volunteering to help with this event, please contact Joyce or Arden.

Introduction to Celestial Coordinates - John Grismore

Using a desktop planetarium program, John demonstrated the basic features of the horizon coordinate system and the equatorial coordinate system. The horizon system provides a convenient, observer-centered method of locating positions in the sky, with azimuth running from 0 (true north) to 360 degrees around the horizon and altitude going from 0 at the horizon to 90 degrees at the zenith. Any point on the sky can be described by the combination of altitude and azimuth. But unfortunately, as the stars and planets move across the sky, their altitude and azimuth coordinates are constantly changing, making it more difficult to describe their exact position at any moment in time.

This is where equatorial coordinates are especially useful. These coordinates can easily be visualized by imagining the latitude and longitude grid on the Earth's surface being projected onto the celestial sphere. Latitude then becomes Declination in equatorial coordinates, and Longitude becomes Right Ascension. This equatorial grid is fixed to the celestial sphere and rotates with the stars and planets as they move across the sky during the night. Therefore, any object in the sky can be located at any time with a fixed combination of Right Ascension and Declination coordinates. These are the coordinates used on star charts, telescope setting circles and Go To scopes.

Exobiology - Virgil Reese

The possibility of life elsewhere in the universe is a topic full of compelling questions and endless speculation. Over time, as our understanding of the fundamental interactions that drive the processes of life has expanded dramatically, and our insights about the mechanisms of evolutionary development have deepened, investigations into the likelihood of exobiology have become more refined and realistic. Discoveries of conditions possibly favorable to life within our own solar system, and in recent years, the steadily accelerating rate of exoplanet discoveries, have transformed the study of exobiology from vague speculation into serious scientific research.

Virgil's presentation began with a fascinating exploration of the diversity of life on Earth, demonstrating that evolution has created creatures far more imaginative and bizarre than science fiction. He then established a list of attributes that are likely to be necessary for life anywhere in the universe. Prime among them is some form of heredity, which can make possible both replication and gradual evolution. He came to the tentative judgement that "multicellular life will probably only evolve on planets (or moons) containing liquid water, in stable orbits around stable, long lived stars." However, life, once established, might evolve the tools (such as intelligence) that could enable it to expand into previously uninhabitable environments.

If extraterrestrial life is common in our galaxy, there are several ways that it could occur. It may arise independently when conditions are right. Recent astronomical evidence suggests that planets are very common around stars in the Milky Way and by some estimates, 25% of the stars may have Earth-like planets. Virgil pointed out though, that as far as we know, life only started once in the 5 billion year history of the Earth. One possibility is that life arises independently all of the time, but that these newcomers are invariably unable to compete against earth's already established organisms. Another possibility is that life is much harder to start than we would like, and beyond the Earth it may be very rare. Various hypotheses for life spreading from star to star (panspermia) have been invoked to offer the hope of more widespread extraterrestrial life, but all of these have significant problems. In addition, they bring us face to face with the Fermi Paradox. If life has spread throughout the galaxy, we should be able to detect signals from intelligent civilizations. Why haven't we?

The thrust of Virgil's presentation was to investigate the likelihood of life that has evolved to a civilization with spacefaring capabilities, since without this, all life is confined to its own stellar system and will disappear at the end of its star's life. His conclusion is that the most likely explanation for our failure to detect such signals is that the probability of life developing elsewhere in the galaxy is quite low.

The program was fascinating and thought provoking. Discussion was lively and enthusiastic, and didn't stop until the library kicked us out of the meeting roomed and closed for the night.

Next Meeting

Monday December 6, John Grismore will present "Observing Asteroid Occultations", in the Bartlesville Public Library Meeting Room. For more information, see the meeting announcement on our website home page at <http://sites.google.com/site/bartlesvilleastronomyclub/> .

BAS Public Website: http://sites.google.com/site/bartlesvilleastronomyclub/

BAS Yahoo Group: http://tech.groups.yahoo.com/group/BvilleAstro/

If you want to have your email address removed from the Bartlesville Astronomical Society mailing list, please send an email requesting removal to bvilleastro@gmail.com .