Tuesdays 10-12 Noon
February 24 and March 2, 2004
D.O.C. House
Of the many objects in our solar system, only three of any significance, our moon and the planets Mercury and Venus, can pass between Earth and the Sun. We are relatively familiar with the Moon causing a solar eclipse - such events are seen somewhere on Earth nearly every year. Transits of Mercury (the planet appearing to cross the surface of the Sun) are more infrequent, averaging only thirteen each century. However, transits of Venus are so rare, that when one occurs on June 8th 2004, no one on Earth will have witnessed the previous one (1882). Indeed, only five transits of Venus have been documented in all of human history!
But rarity is only one attribute of Venus transits. The great English astronomer, Edmond Halley, developed a plan to determine the distance between Earth and the Sun, the astronomical unit, utilizing a transit of Venus. This plan entailed observations from remote sites on Earth. A wealth of fascinating history surrounds ensuing expeditions. For instance, it was to observe the transit of 1769 that Captain James Cook was dispatched to the South Pacific on the first of his three voyages of discovery. To this day, the spot on Tahiti where his party viewed the transit is called Point Venus.
We will begin our study with a look at the inner Solar System and the factors that contribute to solar eclipses and Venus transits. We will gain an understanding of Halley's method for determining the astronomical unit, but this topic will not be made onerous for those who are mathematically challenged! Importantly, the wonderful history surrounding previous Venus transits will be appreciated. Our study will be based on the book, June 8, 2004: Venus in Transit, by Eli Maor, Princeton University Press, 2000. However, all suggested reading material will be provided. Class sessions will be lecture format, with class participation encouraged.
Class is limited to 20 members.
Bob Koester is retired from the telecommunications industry and lives in Grantham. He holds Bachelor's degrees in Music Education and Electrical Engineering from the University of Michigan and an MSEE from New York University. His interest in astronomy is life-long. He and his wife have witnessed total solar eclipses in Baja California (1991) and Aruba (1998). He is not old enough to have observed a transit of Venus!
