Discovery Astronomers Bryce Bolin and Frank Masci discovered C/2022 E3 (ZTF) using the
Zwicky Transient Facility (ZTF) survey, which uses the 1.2-m f/2.4
Schmidt telescope at
Palomar Observatory, on 2 March 2022. Upon discovery, the comet had an
apparent magnitude of 17.3 and was about from the Sun. The comet then was located in the morning sky, at a
solar elongation of 44 degrees. The object was initially identified as an
asteroid, but subsequent observations revealed it had a very condensed
coma, indicating it is a comet. H. Sato reported its coma was 8
arcseconds across in stacked photos he obtained from the
remote observatory in Mayhill, New Mexico, while K. Yoshimoto reported its coma was 15 arcseconds across and the comet had a small tail 25 arcseconds long. The comet in stacked ZTF images appeared extended when compared to nearby stars and was flagged as a comet by the Tails neural network. The comet was
subsequently detected in images taken by
Pan-STARRS 1 in
Haleakalā Observatory, Hawai'i on 10 July 2021, when the comet had an apparent magnitude of 23. The comet had also been photographed without being noticed by ZTF in October and November 2021.
Near perihelion The dust tail and the coma were gradually getting bigger as the comet was approaching the Sun between July and October 2022, and dust production rose from in July to . By early November 2022, the comet had brightened to magnitude 10 and was appearing to move slowly in
Corona Borealis and
Serpens as it moved parallel to Earth. The comet exhibited a green coma and a yellowish dust tail and a faint ion tail. The comet was visible in the early evening and started being visible in the morning sky by the end of November. By 19 December, the comet had developed a greenish coma, a short, broad dust tail, and a long faint ion tail stretching across a 2.5-degree wide field of view. After that, the comet started moving northward, passing through
Boötes,
Draco, and
Ursa Minor, passing within about 10 degrees of
Polaris by the end of January. The comet reached its perihelion on 12 January 2023, at a distance of . The first naked-eye observations of the comet occurred on 16 and 17 January, with the comet having an estimated magnitude of 5.4 and 6.0 respectively. Strong
solar wind from a
coronal mass ejection caused a disconnection event of the ion tail of the comet on 17 January, making it appear broken. On 22 January an
anti-tail became visible. This tail appears pointing toward the Sun and opposite the dust and ion tails. It is caused by particles lying on a disk on the orbital plane of the comet, and when Earth aligns with that plane, they look like a reverse tail.
XMM-Newton X-ray space telescope observed the comet on 23 January, but it was only faintly detected. The comet's closest approach to Earth was on 1 February 2023, at a distance of . As of 31 January 2023, the comet had an
apparent magnitude of about 5; its coma was reported to be about 20' across. The central region of the coma measured bout 4 arcminutes across, which corresponds to diameter of , and featured two jets about 20 arcseconds long. During its closest approach to Earth, it was near the north
celestial pole and located within the constellation
Camelopardalis. The moon was in the
waxing gibbous phase and the brightening moon hampered viewing the comet without optical aid. On 5 February, at the full moon, the comet passed 1.5 degrees from the bright star
Capella. On 6 February, C/2022 E3 (ZTF) visually passed near comet
C/2022 U2 (ATLAS). On 10 to 11 February, the comet passed 1.5 degrees from
Mars and, on 13 to 15 February, passed in front of the
Hyades star cluster. == Scientific results ==