Luckily, Tom Bopp had a cellular phone. He first attempted to call an astronomer at Lowell Observatory in Flagstaff, hoping that a professional sky watcher there could verify the observation and then send an e-mail message to Cambridge. Bopp got an answering machine.
His second call was to an operator. But while he was waiting to get IAU's number, his phone went dead.
The astronomers urged Bopp to hit the road. Call Western Union, they told him. (Sending a telegram is the traditional method for notifying IAU, a practice that is quickly giving way to electronic mail.)
Armed with an estimate of the comet's position, Bopp raced east on Interstate 8, looking for a pay phone. He soon found one, and got a Western Union representative on the phone.
But the rep told him that he couldn't find an address or a phone number for IAU. Bopp hung up in frustration.
It was almost 3 a.m. when Bopp rushed into his north Phoenix home. His wife wasn't thrilled when he threw on the light and started rooting around in a closet. In a pile of astronomy books, Bopp found what he was looking for: the IAU address. He called Western Union, sent a telegram, and went to bed.
At 8:15 in the morning, Bopp was called by Daniel Green of the International Astronomical Union.
"Congratulations," Green said, "you've discovered a new comet."
A few hours later, Green called back, Bopp says, this time with another message: "This thing is really a monster."
In February 1998, guests of honor Tom Bopp and Alan Hale will view a total eclipse of the sun in the Caribbean from the deck of a luxury yacht. Another cruise, possibly to Alaska to view the comet next year, is in the planning stages.
Other benefits of celebrity are beginning to roll in for Bopp. His name is already instantly recognizable among amateur astronomers--when Bopp visited a Tucson telescope store earlier this month, the clerk nearly tripped over himself showing Bopp around, and invited him to be a special guest of the local astronomy club.
Not every comet discoverer experiences such treatment. But then, not every comet is like Hale-Bopp.
Bopp says that the latest estimates of the size of the comet's nucleus--its icy core--is a massive 46 miles across. Most are fewer than six miles across; the nucleus of Halley's Comet, imaged by a satellite which made a close approach in 1986, revealed a ten-mile by five-mile potato-shaped lump. Comet Hyakutake, which came within ten million miles of Earth in March, had a nucleus five miles across.
Sublimating like a piece of dry ice giving off vapor, the nucleus is surrounded by a vast cloud called a "coma." It's the coma that we actually see from Earth, not the relatively tiny icy nucleus. The coma of Comet Hale-Bopp is one of the largest ever seen. Already, still hundreds of millions of miles from the sun, the coma is more than a million miles across. There's still some question whether the comet will sprout much of a tail or put on a spectacular display, but regardless of how it performs, Hale-Bopp will be remembered for its giant size: Scientists find themselves reaching back to the Great Comet of 1811 to find a comet of similar dimensions and orbit.
Yet despite the accolades of scientists and the hospitality of cruise directors, Bopp says he can't help having mixed feelings. He admits that he continually feels a twinge of sorrow for his friend Stevens.
Both of them are unhappy that Stevens' name wasn't also attached to the comet. They point to comets which have carried three names in the past: 1975's Comet Kobayashi-Berger-Milon, for example, or 1983's Comet IRAS-Araki-Alcock, for which two human observers shared credit with IRAS, an orbiting satellite.
But IAU, reacting to sophisticated comet-searching programs developed by professional astronomers, has in recent years followed a stricter set of criteria for adding the names of co-discoverers. Bopp and Stevens complain that IAU, determined to limit the names on a comet to two, has unfairly kept Stevens from his chance at cosmic glory.
Brian Marsden, the IAU's (and the world's) arbiter for discovery credit, scoffs at the notion that it was the IAU's stricter standards which put the kibosh on Comet Hale-Bopp-Stevens. In fact, Marsden says, Bopp is lucky to get any credit at all.
The Sunday morning Bopp's telegram arrived at IAU, a graduate student happened to be there--normally, the office is empty. Since Hale had e-mailed his observation the previous night, Marsden had been able to act on it right away. Confirmation of Hale's discovery came quickly, Marsden says. And if that graduate student hadn't made IAU officials aware of it, credit would have gone to Hale before they'd ever seen Bopp's Sunday telegram.