This column ran in The Tablet in July, 2005
The pictures from Nasa’s Deep Impact mission (see last month’s column) were spectacular. When the space probe hit Comet Temple 1, the heat of its impact made a brilliant flash; even observers on Earth could see it, and then watch the comet’s coma grow bigger and brighter as the dust and ice blasted off the comet spread out away from its nucleus.
The Deep Impact astronomers (who, incidentally, insist they came up with that name before the Hollywood movie!) had planned for a network of observers, professional and amateur, to observe the comet before and after the impact. Here at the Vatican Observatory, we enlisted a dozen students from our  summer school to help out. For two weeks, young astronomers from South America, Australia, and Europe gathered in the domes of our vintage 1935 Zeiss telescopes, perched atop the Pope’s summer home here in Castel Gandolfo, hoping to record an image of the comet’s brightening.
Alas, they had no luck. Though the coma was in theory bright enough to be seen in even a small telescope, its light was lost amidst the ever-growing sky glow of Rome’s light pollution. Castel Gandolfo was once a country village, but Rome has grown out to meet us over the last thirty years. That’s why we’ve had to move our serious observing to a new telescope in southern Arizona.
City lights are the bane of all skywatchers, and especially irritating when so much of it is unnecessary. Street lights and billboards are bad enough, but it’s a rare public building now that isn’t bathed in a garish glow of “security” spotlights. In fact, the lights ruin any guard’s night vision, and create deep shadows where lurkers can hide.
They also blind us to the stars overhead.
A fundamental change has occurred in human culture. When nighttime can be banished by the flip of a switch, “darkness” no longer has the same meaning to us. This changes the way we understand the imagery of classical literature, philosophy, even the Bible. John Staudenmaier, a Jesuit at the University of Detroit Mercy who edits the journal Technology and Culture, suggests that when we no longer have an enforced period of inactivity every night, we also lose an important impetus to pause and reflect on our work, our lives, our families.
Summer is a time for vacations, for just such reflections. For many of us, it is also the only chance we have during the year to get out of the city. If your travels take you under dark skies this season, take a moment to look upwards.
The moon will be rising later and later over the next two weeks; catch it as it clears the horizon and enjoy just how big it appears when you see it next to familiar hills and trees. Keep an eye out for meteor showers – dust spalled off from comets, like the dust ejected by Deep Impact, hitting the Earth in a display of “shooting stars.” If you’re ambitious, learn to identify the major constellations. (Get a book! My favorite is The Stars, by H. A. Rey... well known as the author of the Curious George children’s books.) Take a pair of binoculars, lie down on a hillside, and just explore the Milky Way. Two places where a number of delicate star clusters can be seen are toward the southern horizon (Scorpius and Sagittarius), and northeast in the big “W” of Cassiopeia.
After an earthquake hit Los Angeles on an early January morning in 1994, hundreds of people called up the Griffith Planetarium, wondering why the the sky looked so frightening. It was the first time they’d ever been outdoors with all the power out. How often do most of us see God’s sky the way it really looks?
The date of this posting, August 24, 2015, is just past the first quarter Moon... its light also makes it hard to observe faint objects. But if you wait late enough in the evening, the Moon will set and you'll have an excellent sky for star gazing. You can learn more about protecting dark skies here.