Transit of Venus 2012


This will be only the seventh Transit of Venus deliberately observed by humans. Only two people are known to have watched in 1639. For the transits of 1761 and 1769, observers fanned out around the globe to carefully time the event. Why?

Astronomer Edmund Halley, best known for the comet that bears his name, realized that if two observers, thousands of miles apart on the Earth, carefully measured the time it took for Venus to cross the disk of the Sun, they could use trigonometry to calculate the distance to the Sun. Then, by using Johannes Kepler's Laws of Planetary Motion, astronomers could determine the size and scale of the entire solar system.

While we're not likely to learn more about the solar system's size with this year's transit event, many astronomers are busy watching for planets passing in front of other stars. Sensitive equipment can detect a brief dimming of a star's light, suggesting the presence of a planet. The Kepler spacecraft orbiting Earth has already confirmed dozens of planets, and has data on more than two thousand other possible planets.

Transit Tales: Venus and the Epic Search for the Size of the Solar System

Wednesday, May 16 at 7:30 pm
Monthly Meeting of the Barnard-Seyfert Astronomical Society
Cumberland Valley Girl Scout Council Building
4522 Granny White Pike, Nashville

Only two people saw the Transit of Venus in 1639. In 2012, millions will pause to observe this rare event, either in person or on the internet.

June 5-6 2012 marks only the seventh time in recorded history when human beings will have looked toward our Sun to deliberately witness the planet Venus crossing the solar disk. Observing this rare astronomical alignment allowed astronomers to calculate the distance from the Earth to the Sun. For the first time, we had an idea of just how big space really is.

BSAS member Theo Wellington will delve into the scientific importance, history, and modern benefit of observing transits. Learn how you can safely observe, photograph, and contribute observations of this Transit of Venus. Will you be watching?