Comet C/2025 A6 (Lemmon) on October 28, 2025 UT
Here is a photo of Comet C/2025 A6 (Lemmon) on the early evining of October 27, 2025 PST or October 28, 2025 Universal Time (UT). It was photographed by James Foster with my Askar 103APO (4-inch triplet refractor) at f/4 with ZWO ASI6200MC-Pro full frame color camera, while guiding on the comet's head. The 21 X 60 sec (21-minutes) exposures were stacked and  processed in Photoshop Elements and GraXpert. The rim of green on the head is from diatomic carbon (C2), ion tail is blue and dust tail yellow.  The comet will return to Earth in 1,350 years. .
This is a joint project of James Foster and Michael A. Stecker.
file: Lemon28Oct25Askar-col60-28Oct25-RGBcrop3A_GraXper2EgreenHEAD-JRF1sm.jpg
Click here to see full resolution photo

Photographic Data
date:
October 28, 2025 UT

telescope:
Askar 103APO triplet refractor reduced to f/4
FL= 432 mm

mount:
iOptron CEM60

Guiding on comet's head with SVBony guidescope and ZWO ASI120MM-mini guide camera

imaging camera:
ZWO ASI6200MC-Pro full frame color camera

guiding:
Guiding on comet's head with SVBony guidescope of 240 mm focal length and ZWO ASI120MM-mini guide camera

exposure:
60 seconds X 21 stacked (21-minutes)
.
photographic site:
James Foster observatory at Pinion Pines Estates (Frazier Park California)
(Bortle 4 at 5,500 ft elevstion)



Spectroscopy of Comet C/2025 A6 (Lemmon) on October 25, 2025

Spectroscopy of Comet C/2025 A6 (Lemmon) on October 25, 2025
Here is the spectrum of Comet Lemmon on October 25, 2025 by James Foster with his 13-inch Cassegrain telescope. The rim of the comet's head glows green at about 510 nm from C2 (diatomic carbon). Also abundant at about 388 nm is Cyanide (CN) in the ultraviolet.
file: CometLemon16Oct25Composite2A-JRF-acr2sm.jpg
Click here to see full resolution image

Photographic Data
date:
October 25, 2025

telescope:
13-inch (330 mm aperture) Classical Cassegrain at f/7.5 (home made)
FL= 2,475 mm

mount:
Astro-Physics 1200GTO

camera for spectroscopy:
Atik 414ex CCD camera

spectroscope and camera:
Visual (3700-7400A) Alpy600 with Atik 414ex CCD camera,
IR (6250-10000A) LISA spectrograph in IR mode with Atik 460ex CCD camera. Both were used with 33cm aperture classical cassegrain telescope at F/7.5.
.
photographic site:
James Foster observatory at Pinion Pines Estates (Frazier Park California)
(Bortle 4 at 5,500 ft elevstion)