Monday, 27 October 2025, there was a Falcon 9 launch from California. Sunset was at 1736 MST. The launch occurred at 1743 MST, so it would not have been visible in the bright twilight sky. At 1833 MST, I noticed there was a nice contrail from the launch visible in the western sky.

Open: Tuesday, 28 October 2025, 1804 MST Temperature: 83°F

Session: 2104 Conditions: Clear

Equipment:
12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
Focal reducer

Camera:
D850 DSLR
iPhone 15 Pro Max

Mounted the D850 DSLR camera at prime focus + focal reducer.

1813 MST: LX600 ON, StarLock OFF, High Precision OFF.

1817 MST: The Moon (1/500sec, ISO 400).

I rotated the camera 90° to image more of the tail of Comet C/2025 A6 (Lemmon), focused on the star Vega, and locked the 12" telescope primary mirror.

1826 MST: Wi-Fi ON.

Used SkySafari 7 Pro on the iPhone to slew the telescope to Comet Lemmon.

1828 MST: StarLock ON.

I then began taking images of Comet Lemmon.

1835 MST: Viewed Comet Lemmon, 12x50 binoculars. It was nice, with the tail appearing about 2° long.

1840 MST: Comet Lemmon was faintly visible to the naked eye low in the western sky even with the moonlit sky.

1849 MST: I stepped outside of the observatory and took this handheld iPhone 15 Pro Max photograph (Night Mode, 10 seconds, 1X lens) showing the comet with the telescope pointed at it.

Mouseover or tap on image for pointer

1854 MST: My best DSLR (prime focus + focal reducer, slightly cropped) image of Comet C/2025 A6 (Lemmon) through the telescope (60 seconds, ISO 3200), StarLock autoguided. The comet was getting low in the sky.

1900 MST: StarLock OFF.

Viewed the Moon, 102X.

1908 MST: Stepped outside of the observatory for this handheld iPhone image (slightly cropped) of Comet C/2025 A6 (Lemmon) with the Moon projected onto the observatory dome. The image was taken with the Camera app (Night Mode, 10 seconds, 1X lens)

Although Comet C/2025 A6 (Lemmon) has been fun to see (faintly) and photograph, it has not been as nice as Comet Tsuchinshan-ATLAS was in October 2024, as seen in this iPhone photograph of that comet with the Moon projected onto the observatory dome.

1916 MST: LX600 OFF.

Close: Tuesday, 28 October 2025, 1923 MST Temperature: 71°F

Session Length: 1h 19m Conditions: Clear

---

Comments are welcome using Email. Please read the Email Etiquette guidance.

---

Previous report

Cassiopeia Observatory Home Page