New York, April 4, 1997. The photo was taken with a 35mm SLR
and an exposure of about 30 seconds. (c) Tony Hoffman
Among celestial objects, I have long had a particular fascination with comets, due to their changing appearance, their unpredictability,
their potential to develop into spectacular objects, the fact that many have been discovered by amateurs, and their tendency to wander far
beyond the bounds of the ecliptic to all reaches of the sky. Since 1973, despite living for 25 years in one of the worst places in the world
for observing comets, I have observed 27 of them. (It was the appearance of Comet Kohoutek in 1973 that helped solidify my interest in
Observing comets from New York City is a real challenge, as light pollution is particularly brutal in washing out diffuse objects. Although Comet Hale-Bopp was an obvious naked-eye site from the city, the more delicate Comet Hyakutake--which many observers under dark skies deemed the more spectacular of the two objects--was barely visible here without optical aid. I’m lucky to see a magnitude 7 comet from the city in 20x80 binoculars, while from darker skies I can see two magnitudes fainter than that.
Since 2002, thanks to better equipment and more regular access to dark-sky sites, I have redoubled my comet observing. I have been able to become more involved in making es-timates of the physical characteristics for comets (magnitude, coma diameter, degree of condensation, tail length). I use a range of binoculars, including 22x100, 20x80, 9x63, and 7x50, as well as a 127mm Orion StarMax Maksutov-Cassegrain telescope. It is usually a thrill, and often a challenge, when I go out to try to observe a comet I haven't seen before, and fun when I'm able to track comets over weeks or months, noting their changing appearance and brightness and coming to think of them as old friends before they depart on journeys that in most cases won't bring them back to our vicinity for many human lifetimes.
This page will include links to my articles about comets, as well as brief impressions of many of the comets I have seen, wherever possible augmented by my original observing reports or journal entries (as well as historical facts).
This notorious comet was discovered by Lubos
Kohoutek, a professional Czechoslovakian astronomer working in Hamburg, on
March 7, 1973. It was found seven months before its perihelion, a record at
that time. Its distance from the Sun at discovery, and the fact that it was
expected to pass within the orbit of Mercury (0.14 AU from the Sun) at
perihelion, led astronomers to predict it would be unusually bright, and the
media ran with the story. The approach of Kohoutek was one of the things that
strongly sparked my interest in astronomy. I remember the hype, the claims it
would be the “Comet of the Century.” As is, it became quite bright—the Skylab
astronauts photographed it, using a coronagraph, at magnitude –3 on its
perihelion day, December 28, 1973—but rapidly faded as it emerged into the
evening sky, and in the public's eye it was a total flop. I tried to see it
on January 4, 1974, a night with some thin clouds, with no success. On January 7,
though, I sighted Kohoutek with 7x50 binoculars—my first comet. It was rather faint
(maybe magnitude 3.5 or 4, in twilight and low in the sky, not far from Venus and Jupiter),
like a fuzzy star with a bright center, and a blueish tail of maybe half a degree. I saw it again
the following night (that day I subscribed to what was then a brand-new
) for the
last time; a drawing I did that night indicates a tail length of about 3.5 degrees.
Despite the fact that it did not live up to its predicted splendor,
I remember Kohoutek fondly, as it was my first comet.
A couple of months after Kohoutek passed
through, another comet appeared, one of the first discoveries by Australia’s
Bill Bradfield, who would go on to become the 20th Century’s most prolific
visual comet hunter, with 17 discoveries credited to him (and now one in the 21st Century as well). I first saw this
Comet Bradfield on March 25, the day I’d read about its discovery, as an object
that I estimated at magnitude 4.9 (using the Sidgwick method) with a short tail
in the constellation Cetus. It became circumpolar, I believe, and I observed it
on a number of occasions over the next month. On April 7, I estimated its brightness
at 5.3, with a tail length of about 45 arc-minutes.
On July 25, 1976, I spotted periodic comet
D’Arrest using the 12-1/2" reflecting telescope at Rolnick Observatory in
Westport, Connecticut. The comet was about 10th magnitude (a very rough
estimate) and 2 or 3 arc-minutes in diameter.(A few weeks later, on August 13,
it passed just .15 a.u. from Earth and shone at magnitude 5, its closest and
brightest pass on record—though I only recorded that one sighting in late
Hail, Hale-Bopp, and Farewell
Comet Hyakutake (C/1996 B2): The Great "Earthgrazing" Comet of 1996
Comet LINEAR (C/2001 A2): The Little Comet that Could
Found by fellow SOHO comet hunter Sebastian Hönig quite serendipitously--the first visual comet discovery by a German amateur
in 56 years, since
co-discovered C/1946 K1(Pajdusakova-Rotbart-Weber)--Comet Hönig was well placed in the evening sky for Northern Hemisphere observers in the
late summer of 2002.
Amazingly, it was one of four comets discovered visually by amateurs within six months, while only one such
discovery had been made in each of the previous two years. I first saw Comet Hönig from upstate New York on August 4;
it took me a long and frustrating hour to locate it. I was breaking in my new
127-mm Orion Maksutov-Cassegrain telescope, and I had just gotten a new finder scope for it. The position
I had marked for the comet on my atlas was off by about
a degree, and I was sweeping for the comet, at first being hampered by stray light from a nearby house.
I found the comet soon after they turned the lights off. It was a rather pale and diffuse glow,
obvious when I found it but not easy. It was high in the sky, in Cepheus or maybe Cassiopeia. It was a thrill to view
a comet actually found by someone with whom I'm acquainted.
I saw the comet for the second and last time on August 25, this time in both telescope and binoculars. It had migrated to Ursa Minor, and was located not far from Kochab. I got up the next morning to try to observe Comet SWAN (2002 O6), which had been found by M. Suzuki on SOHO's SWAN images. I went to a nearby field with a relatively clear eastern horizon, but though I scanned the area of Ursa Major where the comet was located--near the stars Tania Australis and Borealis-- in my 9x63 binoculars until morning twilight interfered, I did not see it. I was disappointed; it would have been nice to have had a SOHO comet as the 20th comet I've observed, but I had no such luck. It turned out that SWAN was starting a rapid fading, and within two weeks would be all but invisible in large telescopes. Likewise, Comet Hönig, which had been about 8th magnitude that night, soon faded rapidly, and probably disintegrated by the time it reached perihelion.
Comet Ikeya-Zhang (C/2002 C4)