Every day is Earth Day. For some, however, that date is celebrated on April 22 each year. For those planning activities and events on that date they might consider beginning the day an hour or so before dawn as our two closest neighboring worlds come together in a spectacular display. The crescent Moon and the planet Venus, the two brightest objects in the night sky, will appear to be nearly touching as they rise in the east before the sun.
The Moon and Venus both held an important place in most early cultures on this planet. A close encounter of these brightly shining objects such as the one this month usually attracted much attention.
As we consider our actions and their earthly consequences on Earth Day, we might start the day by viewing this conjunction and even pondering the inhospitable environments on the surface of those two worlds. It may help us to appreciate more the unique and special opportunities afforded us on our planet and the important balances required for sustaining life as we know it.
A close-up view of these two celestial bodies was first experienced by Galileo 400 years ago. In 1609, with a fairly crude telescope, Galileo was able to describe surface features on the Moon and to give a description of Jupiter and four of its moons. His magnified view also revealed the changing shapes of the very luminous planet Venus.
The record of Galileo's observations brought him great personal difficulties in his time but they ultimately provided the evidence that the Earth was not the center of the universe, a notion that was commonly accepted and even enforced in the Western world in his time. This revolutionary concept is one of the great paradigm shifts in human history. Taking humans out of the very central place in the universe was difficult for many.
2009, the 400th anniversary of Galileo's observations, has been designated as the International Year of Astronomy. Efforts are being made in countries throughout the world to bring a greater awareness of the night skies and of the Earth and the place of humanity. Get up early this Earth Day, look in on the brilliant union of the Moon and Venus in the predawn sky, and contemplate our place, and, more importantly, our responsibilities in the great scheme of things.
Tom O'Grady is an instructor in Ohio University's Department of Physics and Astronomy.
4 Opinion
Letter to the Editor
