Eli Maor once drove his family 1,000 miles from Eau Claire, Wisconsin, to Montana to see a full eclipse of the sun. "If you watch one, you want to watch the next one," he explains. "You have to go to really remote places to see it. You have to put yourself in the moon's shadow, which is only 100 miles wide."
In 1991 he traveled to Hawaii to see one, but even though the forecast was for clear skies Maor didn't see a thing because of cloudy weather. He says the 1994 total eclipse he watched from the Andes in Bolivia was "spectacular." In 1995 he traveled 48 hours, to India and back, to witness a 41-second eclipse. On a trip to Mongolia in 1997 the sky show was snowed out. A 1998 eclipse off the coast of Venezuela was successful, but last August's trip to Germany was another wash. "My record is not great," Maor admits. But "if you don't want to take that risk, you might as well stay at home and watch it on TV."
Maor may sound a little obsessed, but he's not one of the worst cases. "There are fanatics who will not miss a single eclipse," he says. They occur once or twice a year, while total eclipses happen every 18 to 24 months. Maor chases only the latter. "The moment it gets total and not one second before, it becomes completely dark and you can see the stars and planets and the corona of the sun. Most people don't realize how abrupt, how sudden the phenomenon is."
Maor, who's a professor of mathematics at Loyola University, has been fascinated by the sky ever since he witnessed a total lunar eclipse as a five-year-old in Tel Aviv in 1942. "From a very young age, everyone else was looking straight. I was looking up." In 1975, after earning a PhD in applied mathematics from the Technion in Haifa, he came to the U.S. to teach at the University of Wisconsin at Eau Claire and was hired by Loyola in '95. The academic life provided him with the flexibility to pursue his hobby.
Ten years ago Maor was reading about eclipses in his collection of astronomy books from the 19th century when he came across a passage that surprised him--a calculation predicting the next transit of Venus for June 8, 2004. The rare event, in which Venus passes between the earth and the sun, occurs in pairs separated by eight years and has only been observed five times.
"The last time it happened was in 1882," he says. "Of course no one who had these books in the 19th century would be alive today. You kind of felt the history kick in you."
As Maor read more historical accounts of the transits, he was surprised at the emotional tones of the normally staid astronomers. "They were aware that no one would watch the transit of Venus until our time. People were becoming aware of their mortality, that life is finite. Measuring your life against an astronomical event, you can really see how insignificant we are."
A fan of nonfiction ("I can't justify reading fiction") and the author of three books on mathematics, Maor was inspired to write a history of observers' accounts of the transits after reading Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time, a 1995 book about the struggle to discover a method for determining longitude at sea. Maor's book, June 8, 2004: Venus in Transit, was published last month. "There's adventure, rivalry, and political intrigue--all the ingredients of making it a great drama," he says.
For example, German astronomer Johannes Kepler, who predicted that a transit would take place in 1631, died the year before it occurred. But 18-year-old English astronomer Jeremiah Horrocks realized that a second transit would take place in 1639 and watched it with a friend. He recorded the event in his diary.
"Clouds interfered and his heart sank," says Maor. "He had duties as a clergyman and had to leave. When he returned a few hours later and saw Venus, he became so moved he could barely contain his emotions."
In 1716, when he was 60, the English astronomer Edmond Halley predicted that timing the exact moments Venus entered and exited the sun's disk could allow scientists to calculate the distance between the earth and the sun. "It was regarded as an extremely important task," says Maor. Consequently, for the next transit, in 1761, 70 observation stations were set up around the globe in places such as Siberia, the Cape of Good Hope, and Sumatra as part of a rare international effort to record it--despite such obstacles as the Seven Years' War. Maximillian Hell, an Austrian priest who spent a year away from home to watch the transit from Norway, took so long to write his report of the event he was accused of falsifying his findings and wasn't exonerated until 100 years later. A Frenchman named Le Gentil undertook an expedition to Pondicherry, a French colony in India, to watch the transit. Just before his arrival the colony was taken over by the English, so Le Gentil sailed to the island of Mauritius instead, then known as the Isle of France. Unfortunately, bad weather thwarted his observation plans, so he stayed on until the next transit eight years later--only to be hampered by cloudy skies once again. When he finally returned home, he learned he had been presumed dead and that his estate had been divided among his relatives. Captain James Cook's 1769 expedition to the South Pacific island of Moorea nearly ended in disaster when locals stole observation equipment days before the transit.
Those efforts, as well as subsequent attempts in 1874 and 1882, rendered imprecise results due to bad weather and an optical illusion known as the black drop effect, which obscures the exact moments when Venus crosses into and out of the sun.
"Now you can use radar and other techniques that give much better accuracy," Maor says, while noting that the 2004 transit will be the first that most people will watch for the spectacle rather than for scientific reasons. He will probably go back to Israel to observe the event, which will be visible in the eastern hemisphere and in part from the east coast of the U.S.
Maor cautions that the transit should only be viewed through a filter. "You will see a small black dot or circle entering on the sun's disk slowly moving east to west for about six and a half hours. It's nothing like a total solar eclipse. It's not that dramatic, but the rarity of it and the whole history of the event are what make it exciting."
Last November, Maor set up a telescope in the driveway of his Morton Grove home and tried to watch a transit of Mercury, which happens about 13 times a century. Again clouds interceded. As for June 8, 2004, the weather could go either way. "You can predict an event 100 years into the future, but you cannot predict weather sometimes even a day ahead of time. Astronomy is a precise science. Meteorology is a different story."
Maor will discuss June 8, 2004 Tuesday at 7 at Borders Books & Music, 830 N. Michigan (312-573-0564). It's free.
Art accompanying story in printed newspaper (not available in this archive): photo/Jim Newberry.