Almanac: Comet Hunting
In ancient times, people were well aware of the regular movements of the heavenly bodies and thought that the positions and motions of the sun, moon, and planets influenced affairs on the earth. It was troubling, therefore, when things happened in the sky that weren’t predictable or usual. Such events were generally interpreted as omens of famine, drought, or some other catastrophe.
One of the things that most often caused a stir among the ancients was the appearance of objects that looked fuzzy or which trailed what looked like smoky tails. Such objects reminded some people of a woman running, her long hair streaming out behind her. The Greek word for “long hair” is “kometes” and that’s what they called the objects. The Romans modified that idea slightly, calling the objects “stellae cometae” meaning hairy stars. Today we simply call them comets.
In 1704, Edmund Halley de-mystified comets by showing that they obeyed the same rules of physics as any other celestial body, and thus their orbits could be predicted accurately. A comet with an orbital period of roughly 76 years was named for Halley, and the last time it neared Earth I made some effort to see it.
This involved driving a wheezing old station wagon from Portland, Oregon to a 6800-foot mountain near the Mexican border in Arizona. The mountain was Kitt Peak, at the top of which is a set of observatories and at the bottom of which was a sign forbidding trespass. I had come a long way, by that time—April 11, 1986—and I wasn’t in a particularly law-abiding frame of mind. So I drove nearly to the top, parked, and waited for night to fall.
An hour of peering, and of twisting a star chart this way and that in an attempt to relate the chart to the starry sky resulted in nothing but a stiff neck. The air was perfectly clear, the sky very dark, and the stars glorious, but I could see no sign of a comet. Phooey.
At 3 a.m. I was awakened from slumber in the back of the station wagon by headlights in the windows and the sound of tires on gravel. I figured I was about to be busted, but it turned out to be another illegal comet hunter. This guy knew right where to look. He pointed to what looked to the naked eye to be barely a star, let alone the infamous comet. But sure enough, seen through the binoculars, the comet was obviously non-starlike. It was pretty large, actually, but it was roughly spherical with no trace of a tail because we were looking at the comet end-on rather than from the side. The Great Halley’s Comet looked like nothing but a frayed ball of cotton.
Although thousands of comets with known orbital periods have been discovered, new comets are discovered every year and, sometimes, put on a show rivalling any of the famous comets of yore. The most recent of these—and the only comet I’ve ever seen that actually looked like a comet—was NEOWISE, which could be seen with the naked eye in July, 2020, and which was beautiful in binoculars. In January of this year a comet was discovered by G. J. Leonard and looked as though it might come near enough to earth to put on a show. But with an orbital period of about 80,000 years, nobody could tell what it would look like.
Comet Leonard came closest to earth last week—December 12, to be specific—and so I went out looking for it on the two nights that were clear. This time I didn’t need to trespass—I went to my favorite west-facing stargazing spot, Mt. Pollux in South Amherst. This time my star chart was on my phone, not a piece of paper, and I had the unmistakable beacon of Venus dazzling low in the west after sunset to serve as a marker. The comet was supposed to be visible below and to the right of Venus, near the horizon.
The sky on my first attempt was clear, but conditions were not ideal because the moon was up and getting near to full, which washes out fainter stellar objects. The light pollution from nearby towns also washed out the sky a bit. But I have a good pair of binoculars and have seen many faint objects even under less-than-ideal conditions, so I was hopeful. Alas, after many minutes of scanning, then waiting for the sky to darken more for repeat scanning, I saw nothing. The next night conditions had deteriorated a bit—the air was thicker and thin clouds obscured the area around Venus periodically. Again I drew a blank. My only consolation was a lovely ring around the moon, which heralded the warm front that brought rain a day later.
Now Leonard is nearing the sun and is no longer visible without a telescope, and after it rounds the sun on January 3 it will be visible only to folks in the southern hemisphere. Ah well! So it goes with comet hunting—at least at the amateur level I participate in. I’m sure there will be more comets to hunt in the future, and—who knows?—maybe I’ll make it to July, 2061 to see Halley’s Comet once more. I’ll be 104 years old, true, which might slow me down some. But with a little luck and advanced medical technology, it doesn’t seem like an unreachable goal. And this time Halley’s will be much closer to Earth than it was in 1986, so maybe it will redeem itself with a properly majestic display.
Almanac is a regular Indy column of observations, musings, and occasional harangues related to the woods, waters, mountains, and skies of the Pioneer Valley. Please feel free to comment on posts and add your own experiences or observations.
3 thoughts on “Almanac: Comet Hunting”
I had a similarly disappointing experience in San Diego (atop Mt Palomar) with the 1986 visit of Halley’s Comet, but the spectacular appearance of comet Hale-Bopp in 1997 made up for that manifold!
Besides the sky-show comets offer to us humans (and perhaps other celestially-curious creatures), they collectively are thought to have delivered the vast fraction of water and organic material to the otherwise rocky inner planets of the solar system like Earth.
And inasmuch as water and organic compounds are essential to life as we know it, the search for extra-terrestrial life in other star systems within our galaxy may turn on the question of whether or not those systems also have an abundant cloud of comets orbiting them (as our star Sol is surrounded by the Oort Cloud).
Something to think about on wintery-mix day, like a rain of mini-comets ….
Thanks for that information Rob! I missed Hale-Bopp…was consumed with child-rearing and other mundane matters and was living in Cambridge, not the darkest of skies. I love that people keep discovering new comets…celestial gifts, for sure!
Don’t Look Up – Comet Dibiasky is headed right at us from the Oort Cloud.
Learn everything you need to know about it on Netflix.