The year is off to a great start for comet hunters as what could be the best comet of 2023 will now take center stage in January and February. Comet C/2022 E3 (ZTF) will make its closest approach to the Sun on Thursday, January 12. Then, after orbiting the Sun, it will make its closest approach to Earth on Wednesday, February 1.
Here’s everything you need to know to see Comet C/2022 E3 (ZTF) as it moves across the sky.
Where did comet C/2022 E3 (ZTF) come from?
Comet C/2022 E3 (ZTF) was first discovered in March 2022 by the Zwicky Transient Facility (ZTF), which scans the entire Northern Hemisphere sky once every two days from the Palomar Observatory in California. You may have noticed that many other comets also have the acronym ZTF in their names. This is because they were discovered by the same facility.
C/2022 E3 began its long journey to the far outer reaches of the Solar System, within Oort cloud. The comet will make its closest approach to the Sun, or perihelion, on January 12, when it comes within 1.1 AU of our star. (One astronomical unit, or AU, is the average Earth-Sun distance.)
Although being closer to the Sun can make some comets intrinsically brighter, at perihelion, C/2022 E3 will still be 0.71 AU from Earth, meaning it will probably not reach visibility with the naked eye this a moment.
After orbiting the Sun, C/2022 E3 will continue to brighten until the end of the month. The comet’s brightness is projected to peak around February 1, when it makes its closest approach to Earth, passing about 0.28 AU from our planet. At this point, many observers and astrophotographers are hoping that C/2022 E3 will reach naked-eye magnitudes as it passes through a particularly rich region of the sky near the north pole, setting the stage for some wonderful pictures.
Even at its brightest, Comet C/2022 E3 (ZTF) is not expected to form a bright, long tail visible without a telescope. Still, even without a tail, the comet will be a sight to remember. Also, comets can always surprise us with unexpected bursts, so it’s worth following the progress of C/2022 E3 to see what it does!
How to see Comet C/2022 E3 (ZTF)
Comet C/2022 E3 (ZTF) reaches perihelion on January 12. Around 4am you can find her high in the northeast, floating in the Corona Borealis constellation. Alison Klesman (via TheSkyX)
Currently visible to observers in the Northern Hemisphere, the best time to view C/2022 E3 is early morning just a few hours before dawn. The comet’s brightness is now around magnitude 7, making it easily visible through binoculars or any small telescope. And if the comet brightens to magnitude 6 or better, C/2022 E3 will be visible to the naked eye under good conditions.
As the comet approaches the Sun this week, the waning moon dominates the early morning sky, reducing visibility. However, it’s worth trying your luck tracking it down with binoculars or a telescope.
Try zooming in on the green-tinged orb as it springs from its current residence in the Corona Borealis up through Boötes and Draco, passing through Ursa Minor near the cup of Ursa Minor at the end of the month. As C/2022 E3 passes through the inner solar system and passes by Earth, it will appear to cover large swathes of the sky each day, tracking close to the Pole Star, Polaris. By the time C/2022 E3 passes close to Earth in February, the comet will lie in Camelopardalis.
This week, C/2022 E3 rises in the northeast around midnight, climbing higher in the sky as dawn approaches. This makes it best for early morning watchers. However, if you’re willing to stay up late next week, starting January 16, you can try to spot the comet before the moon rises around 2 a.m. local time. (Note that C/2022 E3 won’t be very high in the sky at this time, so you’ll want to get up high and choose a viewing spot with a clear view of the northeastern horizon.
Until January 18, without the Moon interfering, C/2022 E3 will rule the morning sky. It will then travel through the northeast Volovar headed for Draco. Along the way, on January 23, the comet will pass northeast of the galaxies M102 and NGC 5907. A day later, each comet’s broad tail will narrow rapidly (within about a day) as the comet’s orbital planes and the Earth’s cross . Just as quickly, however, the tail will appear to extend back after the crossover.
On the last day of January, C/2022 E3 is only 11.5° from Polaris and moving at speed. The comet will cover about 12″ per minute, forcing astroimagers to choose shorter exposures if they want to capture sharp details.
Comet ZTF covers huge swathes of the sky each night later this month, passing close to Polaris before heading towards Camelopardalis. Astronomy: Roen Kelly
Shortly after C/2022 E3 makes its closest approach to Earth, the comet will become visible in the southern hemisphere. The comet will then fade over time as it moves away from the Sun and into the outer solar system. And scientists are still not sure if it will ever come back or not.
To follow C/2022 E3 across the sky and discover other timely goals and events, be sure to check out our Heaven this week column updated every Friday by 9 a.m. CT.