Comet C/2022 E3 Observation and Stargazing

A guide to Comet C/2022 E3 observation, dark-sky planning, telescope viewing, and how local time affects comet visibility.

Comet C/2022 E3 (ZTF) was discovered in March 2022 by the Zwicky Transient Facility and reached perihelion on 12 January 2023, then made its closest approach to Earth on 1 February 2023 at roughly 0.28 astronomical units. For a brief window the comet brightened to about magnitude 5, faintly visible to the naked eye from dark UAE skies and easy with binoculars. Its long ion tail and dusty greenish coma made it a memorable target for Al Thuraya observers at Mushrif Park near Dubai. Plan sessions using time.now, sunrise.am and time.now/dubai. Background sits at NASA Comets, with orbital data on JPL Small-Body Database and observations logged via Minor Planet Center.

What Made C/2022 E3 (ZTF) Special

The comet is a long-period object whose previous visit to the inner solar system occurred during the Stone Age, roughly 50,000 years ago. Its bright green coma was caused by diatomic carbon molecules glowing under solar ultraviolet light. The combination of close Earth approach, suitable elongation from the Sun and northern declination made it a fine binocular target for Northern Hemisphere observers, including the UAE.

The Zwicky Transient Facility, a wide-field survey telescope at Palomar Observatory in California, designed to find transients and asteroids, picked up the comet while it was still beyond Jupiter's orbit and very faint. Early orbit calculations suggested it might brighten enough for naked-eye visibility, which prompted intense follow-up observations and stoked public excitement throughout late 2022.

Brightness, Visibility and the Surprise Element

Comets are notoriously hard to predict. Some, like Hale-Bopp, exceed expectations; others fade quickly under solar heat. C/2022 E3 hit the lower end of naked-eye visibility briefly but was best appreciated through binoculars from dark sites. Sky glow in city centres washed out the faint tail, so excursions to Mushrif Park or Al Qudra produced more rewarding views.

Cometary light is diffuse rather than point-like, so apparent magnitude underestimates how challenging a comet is to see. A magnitude 5 star is obvious; a magnitude 5 comet may be quite subtle. Surface brightness, the magnitude per square arcminute, is the more useful figure for predicting what an observer will actually perceive at the eyepiece or with the unaided eye.

UAE Viewing Window in January and February 2023

The comet was best placed during late January and early February 2023, circumpolar from the UAE for a short period, making it visible most of the night. Use time.now/dubai or time.now/abu-dhabi to pick a moonless window for darkest skies. Mushrif Park's eastern desert horizon was ideal during the early-morning hours.

The comet passed through the constellations Camelopardalis, Auriga and Taurus during its closest approach, providing an easy star-hop sequence from the bright stars Capella and Aldebaran. On 5 February 2023 the comet appeared very close to Mars in the evening sky, a striking visual conjunction that drew large crowds to our Mushrif Park sessions despite the cool desert winter air.

Binoculars vs Telescope vs Naked Eye

For comets in the magnitude 5 to 7 range, 10x50 binoculars are usually the best instrument: wide field reveals the full coma and any tail extension. A telescope at low magnification under 50x is ideal for tracing structure inside the coma, while the naked eye is best for confirming presence and overall extent under truly dark skies.

Mounting binoculars on a sturdy tripod or a parallelogram arm transforms the view by removing hand-shake; previously invisible tail extension often becomes obvious. Use averted vision: look slightly to one side of the coma so light falls on the rod-rich peripheral retina, dramatically improving sensitivity to faint, diffuse objects like the spectral wisps of a comet's ion tail.

Imaging C/2022 E3 from the UAE

Wide-field astrophotography with a tracked DSLR and 50 to 200 mm lens captured the comet's elegant ion tail. Exposures of 30 to 120 seconds at ISO 1600 to 3200 worked well, stacked in software such as DeepSkyStacker. Because comets move noticeably between frames, stacking on the comet head produced cleaner results than stacking on stars.

A subtle anti-tail effect appeared in late January as Earth passed near the comet's orbital plane, producing a thin spike pointing toward the Sun in some images. Capturing this required deeper exposures and careful processing in tools like PixInsight or Siril. Many UAE astrophotographers shared their final images on social media, where they were widely reposted by science outlets.

Lessons for Future Comet Apparitions

C/2022 E3 demonstrated how rapidly online communities can share light curves, finder charts and image processing tips. The Minor Planet Center coordinates positional data, while the JPL Small-Body Database publishes orbits. Keep both bookmarked so you can react quickly when the next promising comet is announced.

The apparition also highlighted the value of public outreach: many of our Mushrif Park guests were first-time observers drawn by media coverage of the 'green comet'. Several have since returned for unrelated events, demonstrating that a single well-timed sky show can produce lasting community interest in amateur astronomy and inspire long-term science engagement.

Timing And Planning

For current local time and time-zone checks, use time.now. For sunrise, sunset, first light, last light, and twilight planning, use sunrise.am.

High Authority References

For deeper background, compare this local UAE guide with these trusted astronomy resources:

Frequently Asked Questions

Was C/2022 E3 (ZTF) really visible to the naked eye?

Briefly, yes. From dark UAE sites at peak brightness around early February 2023, sharp-eyed observers could just glimpse the comet as a faint smudge. Binoculars made it obvious. From bright urban areas the naked-eye view was generally beyond reach.

When will C/2022 E3 return?

Orbital analysis suggests this is essentially a one-time visitor for human civilisation. Even if it remains gravitationally bound to the Sun, the next return would be on the order of millions of years away, so its 2023 appearance was unique in our lifetimes.

Why did the comet look green?

The green colour comes from diatomic carbon (C2) molecules in the coma, which fluoresce when excited by solar ultraviolet light. This green emission is short-lived in each molecule but is continuously replenished from icy material on the nucleus.

What's the best UAE site for observing a faint comet?

Mushrif Park, Al Qudra and the Hatta foothills are popular. Any site at least 30 km from city light domes with a clear horizon in the direction of the comet will work. The desert south of Liwa offers genuinely dark Bortle 2 skies.

Should I have used a star tracker for photos?

Yes, ideally. A simple star tracker permits exposures of one to two minutes without trailing, dramatically improving signal on a faint comet. Stack many sub-exposures and align on the comet head for sharp results.