Catch Comet C/2020 V2 ZTF in the pre-dawn sky in July

Late July will be the best time to see the brightening comet this month.

By Pete Lawrence

Published: Saturday, 01 July 2023 at 12:00 am

Comet C/2020 V2 ZTF is currently visible through a telescope or large binoculars in pre-dawn skies.

At the start of July 2023 it is near Uranus, but the bright post-solstice sky may thwart attempts to see it properly.

As darkness returns, the comet shyly heads south to end the month east of the distorted pentagonal shape representing the head of Cetus, the Whale.

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"Ninth
Ninth magnitude comet C/2020 V2 ZTF starts July 2023 near Jupiter and Uranus. Starting at mag. +9.4, it’s expected to reach +9.1 mid-September, thereafter fading again. Credit: Pete Lawrence

Although Comet C/2020 V2 ZTF will brighten in July 2o23, the bad news is that it’s not by much, starting the month at mag. +10.0 and ending it at +9.8.

The balance between position and sky brightness will be a tricky one and it’s probably not going to be a viable target until the last week of July.

Even then, it will remain challenging to view from more northerly locations.

As the end of the month approaches, the darker sky and the more elevated position of the comet before morning twilight engulfs it should make it a potential target in the early hours.

"Chart
Chart showing the location of Comet C/2020 V2 ZTF from July – September 2023. Credit: Pete Lawrence

The Moon is in its first quarter phase on 25 July and although it tries to encroach on the comet at the very end of July, it should be possible to grab a short window of relative darkness after moonset.

The Moon will then interfere badly at the start of August (something we can happily put up with because it means it will be out of the way in mid-August, when the Perseid meteor shower reaches its peak).

As the Moon moves out of the way again in August, the comet will be in a better observing position, attaining a higher altitude in darker skies around mid- to late August.

Throughout much of August 2023, Comet C/2020 V2 ZTF is predicted to reach a magnitude of around +9.1, continuing its southern motion and ending the month near the mag. +3.9 star Eta (η) Eridani.

Have you managed to photograph Comet C/2020 V2 ZTF? Don’t forget to send us your images.

This guide originally appeared in the July 2023 issue of BBC Sky at Night Magazine