The Arrival of Hale-Bopp!
The waiting is over, and what may turn out to be the comet event of the century is about to grace our night skies. Comet Hale-Bopp was named after its discoverers Alan Hale and Thomas Bopp who first saw the approaching comet in July 1995. Since then the astronomical community have been speculating and excitedly waiting the arrival.
. Comets come from the outback of the solar system, in a place well beyond the orbits of the most distant planets, in a place called the Oort cloud. Here, chunks of rock and ice, left over junk from the formation of the solar system, orbit for eons. Then, something happens to disturb their silent orbits. Perhaps it is a gravitational nudge from a passing planet or star. The chunk is pushed into a new orbit, and sometimes that sends it in toward the Sun. Out here, they have no characteristic tail, that comes later when it is closer to the Sun. They are also quite small, and are not often detected until they are quite close. Most comets are not visible to the unaided eye. The appearance of Comet Hyakutake last March was a rare event, the fact that a year later we have a chance at an even brighter comet is truly of astronomical proportions.
There are a number of things about Hale-Bopp that lead astronomers to believe this comet will be a sight to remember. It all started with the discovery, when the comet was found much farther out than other newly discovered comets. Then came the comet's brightening, at a greater rate than any other observed comet. And then the comet became visible to the unaided eye while still beyond the orbit of Mars.
It is true that comets can be unpredictable things, and more than a few comets have been disappointments. The most recent visit of Halley's comet is a good example. The Earth happened to be on the opposite side of the sun when Halley reached peak performance and we got a poor show. Another factor is how many trips the comet has made in and around the Sun. Each time the comet comes in, it loses gasses as they are heated and vaporized by the Sun. Hale-Bopp has a very large orbit that has made few trips into the inner Solar System.
So when and where do you look to find comet Hale-Bopp? The comet will be visible to the unaided eye all of March and April. During most of March, the comet will be visible in the morning sky. The comet rises about 4 hours before the Sun. You can spot the comet easily in the northwest sky. It is almost as bright as the brightest stars in our sky. The tail is forming and may take up about 10 degrees in the sky.
19th the moon enters the morning sky and after that Hale-Bopp starts to
sink in the northeast sky. After March 21st, the comet will be visible
in the evening sky and in the predawn sky. The comet's closest approach
to Earth is on the night of March 22nd. It will be a little farther from
us than the Sun, but because the comet is so big, it will still be a spectacular
It is in April that the comet reaches its peak. Just what the peak will be is still being wrangled over in the astronomical community. Brian Marsden of the Central Bureau for Astronomical Telegrams at Harvard, believes the comet will be a superb sight. Marsden has said all along that the comet would be a spectacular sight. While many other astronomers were fretting over the unpredictability of comets, Marsden remained firm. "Observers who had really dark skies were thrilled with Comet Hyakutake. Comet Hale-Bopp will be great for the more typical suburban and, perhaps even city dwellers, I honestly don't see how it can fail us."
Comet Hale Bopp may well turn out to be the brightest comet of the century. It could even be more impressive than the great comet of 1577, a comet that is pictured in many paintings around the world. It was a brilliant object that stayed in the sky for several months. Brian Marsden believes Hale Bopp may at least compete with that great comet. "I don't want to create the impression that Hale-Bopp will be the best comet since 1577, for after all, it is a long way away in comparison with intrinsically fainter comets that came much closer to the earth and sun. But there is also the point that, if Hale-Bopp DOES turn out to be like the great comet of 1811, that greatness may well show best in April, i.e., AFTER most predictions are putting it at its best (late-March)."
During April the comet will be in the night sky and at its peak. The moon will interfere with viewing part of the month. Full moon is on the 22nd and just before and after this it will be more difficult to see the comet and certainly much harder to see any detail in the tail. The comet will be in the northwest sky, and during the month will move more toward the west-northwest sky.
Use the finder
chart, though the comet will be very easy to find. You will not need binoculars
or telescope. If you do have them, you might use it to get a better look
at the head, but all you really need is your eyes. At peak the comet's
tail may stretch 20 or more degrees across the sky.
Copyright © 2001 Kathy A. Miles and Charles F. Peters II