As 2002 draws to a close, a faint periodic comet should be visible through telescopes in the evening sky, making its first predicted return. Comet Brewington (154P/1992 Q1), discovered some 10 years ago, could reach 10th magnitude early in the New Year.
The mid-1980s through mid-1990s were a golden age for North American amateur comet hunters — and not just for the number of new comets that were found during that time frame. California amateur Donald Machholz discovered two comets that orbit the Sun in less than six years each, while Sky & Telescope contributing editor David Levy snared one that visits the inner solar system only every 50 years. In 1992 at Cloudcroft, New Mexico, Howard Brewington chanced upon this year’s returning sojourner.
In the morning hours of August 28, 1992, with no Moon to interfere, Brewington swept up in his 40-centimeter (16-inch) Newtonian reflector what he later described as "the smallest and faintest comet I’ve ever seen" (Sky & Telescope: November 1992, page 493). This was his fourth comet discovery in less than three years, and it had the distinction of being the first for which no other observers shared the credit.
It was a month later that astronomers realized that Brewington’s new comet was actually of short period, only a little more than 10 years. It had passed through the perihelion point of its orbit (its nearest point to the Sun) on June 7th. For Comet Brewington, this point was beyond Mars’s orbit.
Comet Brewington faded much more sharply than most comets as it receded from the Sun in 1992, complicating any forecast of its brightness this time around. In 1992 it was not observed at all until 11 weeks after perihelion, so there is some interest in how Comet Brewington will fare during the early stages of its return voyage.
Observations made in early January put the comet at 12th magnitude, slightly fainter than originally predicted. As Comet Brewington moves closer to its moment of perihelion on February 19th, its angular distance from the Sun steadily shrinks. However, Northern Hemisphere observers should be able to follow the comet through Aquarius and Pisces, where it will perhaps peak at 10th magnitude in February.