ZTF, the "Green Comet"

By the end of 2022 it was scheduled to be spectacular, with a potential of being visible to the naked eye in February, but it didn't... Nevertheless, comet ZTF (C/2022-E3), named after its "discoverer" (Zwicky Transient Facility), is an interesting object, since it is returning supposedly for the first time in some 50,000 years ! Indeed it must have witnessed some great changes in our civilisation...

We could observe it wandering from Gemini to Taurus, still shining at a magnitude of 6.4, that is just under the limit of visibility for human eye.
The picture below shows the bright, extended coma (left side) followed by the flared, irregularly shaped dust tail (right side). The green color of the coma, rather common on comets, is due to the presence of diatomic carbon (C2), while the brownish (reddish?) tint of the tail is produced by the usual interaction of sunshine with dust.

Photo: Cristian Valenzuela / Observatorio del Pangue - February, 2023
Canon 60D at prime focus of SCT Meade LX200 16" reduced at f/6, ISO 3200, total exposure 10 minutes.