Comet C2022 E3 ZTF in February 2023

The comet C/2022 E3 ZTF was recently visible on February, 7th from Bad Kreuznach, Germany, where the nights before were mostly overcast since the beginning of the year 2023. The comet was discovered in March 2022 by a professional wide-field survey observatory, the Zwicky Transient Facility as indicated by its name. The comet passed perihelion (closest approach to sun) on January 12th, 2023 and ran through the perigee (closes approximation to Earth) on February 1st, 2023 when it also reached its maximum apparent brightness of roughly 5 magnitudes. Thus in an urban area it could not be seen by the naked eye the moon being close to full around that date. The following image was captured shortly after the perigee passage on February 7th, 2023 at night.


Comet C/2022 E3 ZTF, 2023-02-07 around 21h UTC, 19x120s RGB, 3x300s RGB for background, setup: Atik 460EXmono, Lacerta Newton 10"f/4, Bad Kreuznach, Germany

Where the comet was roughly located at the time when the exposures were taken can be seen from the map overlay below.


With Skymap Overlay: Comet C/2022 E3 ZTF, 2023-02-07 around 21h UTC, Bad Kreuznach, Germany

Seen at a focal length of 1000mm the comet moves rather fast with respect to the background stars. Therefore the image was shot in two steps. The most time was spent doing exposures while guiding the telescope mount by the comet's nucleus. Only one exposures was done at 300s for each color channel to provide an un-blurred view of the background sky. The comet's image and the background was processed separately and re-combined by the image processing.