When I "retired" from systematic visual comet observing at the end of 2024 I did so with the caveat that I might occasionally "come out of retirement" for bright and/or interesting comets, and accordingly I expected to add additional comets to my tally from time to time. I never really thought, however, that I would completely fill up a ten-entry page and start a second such page in less than a year, but with the flurry of "bright and/or interesting" comets that appeared during the latter months of 2025, here I am . . .

This particular comet is an intrinsically faint short-period object that I have seen on three previous returns, beginning with its discovery return in 2003 (no. 335) and then in early 2009 (no. 446) as a part of "Countdown" and more recently in 2020 (no. 677). In my write-ups for both the 2008-09 and 2020 returns I noted that the return this year would be a relatively favorable one, and in due course the comet was recovered on July 20, 2025 by the Pan-STARRS survey in Hawaii, about three weeks before it went through opposition. It remained primarily within southern hemisphere skies afterwards and was imaged on a fairly regular basis, and I successfully imaged it a couple of times (in mid-September and early October) via the Las Cumbres Observatory network when it was still a relatively faint object near 18th magnitude. It apparently began to brighten somewhat rapidly after that, and when the final images were obtained by observers in the southern hemisphere at the beginning of November before it entered evening twilight, it was near 12th to 13th magnitude.

Comet Christensen was nearest Earth (0.43 AU) on November 9 and went through inferior conjunction with the sun about a week later, and by the last few days of November began emerging into the northern hemisphere's morning sky. The earliest post-perihelion images I'm aware of were taken on the 26th, when its elongation was 26 degrees, and showed it as being between magnitudes 9 1/2 and 10. The comet's elongation has been steadily increasing since then, but in all honesty in my current state of "retirement" I wasn't sure I would bother looking for it. However, on the morning of December 2, when I was already up to obtain one final observation of Comet 3I/ATLAS (no. 769) -- now having faded slightly, to a bit below 10th magnitude -- before the full moon, I decided I would go ahead and try for it (with its elongation having by then increased to 34 degrees), and after it had emerged from behind the trees I have in that direction I successfully detected it near the beginning of twilight as a small and moderately condensed object near magnitude 10 1/2.

Comet Christensen is presently located in southeastern Virgo 2 1/2 degrees east of the star Kappa Virginis and is traveling towards the northeast at slightly over 20 arcminutes per day, gradually curving more directly eastward. As it continues pulling away from both the sun and Earth its elongation hereafter increases more slowly, to only 44 degrees by mid-December and to 54 degrees by the end of the year; meanwhile it will likely fade quite rapidly. With all this, and with the bright moon now in the morning sky, it is rather unlikely that I will look for it again. But, to address the thoughts that I expressed at the end of my write-up for its 2020 return, I was indeed able to grab at least one observation of this comet this time around . . . and, for whatever it's worth, this turns out to be the brightest observation I have ever made of it.

INITIAL OBSERVATION: 2025 December 2.52 UT, m1 = 10.4, 1.4' coma, DC = 4-5 (41 cm reflector, 72x)

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