A green comet is passing by Earth. Here’s how to see it. (2023)

Later today, a visitor from the solar system’s frigid outermost regions will come within 26 million miles of Earth: a ball of ice and dust that will glow in our skies with an emerald gleam.

For the past several months, the recently discovered comet C/2022 E3 (ZTF) has been dazzling stargazers and astrophotographers, with the excitement ratcheting up in recent weeks. On the evening of February 1, the comet is making its closest approach to Earth in 50,000 years—providing a vibrant glimpse into one of the building blocks of our cosmic home.

Where did this comet come from, and how can you see it for yourself? We’ve got you covered.

(Video) How to see 'Green Comet' passing over Earth this week

Where did the comet come from?

C/2022 E3 (ZTF) hails from the Oort cloud: an icy hinterland on the outskirts of the solar system where hundreds of billions to trillions of comets lurk, frozen leftovers from the planets’ formation more than 4.5 billion years ago. According to In-the-sky.org, it made its closest approach to the sun on January 12, coming within 103 million miles (166 million km) of our home star. (Learn about the differences between asteroids and comets.)

Matthew Knight, a comet astronomer at the United States Naval Academy in Annapolis, Maryland, says the comet’s trajectory at its moment of discovery implied an orbital period of roughly 50,000 years. Rewinding the clock, the last time this comet passed this close to the sun, Earth was in an ice age, and Neanderthals and mammoths were still alive and kicking.

However, as comets heat up in the sun’s glare, they release gas and dust, which can change their trajectory through the solar system. For that reason, Knight warns that it’s impossible to say with certainty for how long C/2022 E3 (ZTF) had been orbiting the sun along its inbound path.

What we do know, though, is that the comet is white-knuckling its way through the inner solar system right now. Later today, when it comes within 26 million miles (42 million km) of Earth, it’ll whiz past us at a relative velocity of more than 128,000 miles per hour (207,000 km/h), according to NASA’s Jet Propulsion Laboratory.

I’ve heard that the comet’s green. What’s going on there?

This comet is green because its coma—the gassy shroud surrounding its nucleus—contains a reactive compound called diatomic carbon (C2), which is bright in green wavelengths of light. This green color doesn’t carry into the comet’s tail because C2 breaks down in sunlight, with a single molecule surviving slightly less than two days on average.

(Video) How to see Comet 2022 E3 (ZTF), the Green Comet

The color of C/2022 E3 (ZTF) isn’t unique: Most comets that have higher gas contents tend to yield C2, so they “are generally going to look green to our eye,” Knight says. That said, only a subset of comets happen to make it as close to Earth as C/2022 E3 (ZTF) will get, so it’ll provide an uncommonly good view of a comet’s emerald hue.

How can I see C/2022 E3 (ZTF)?

Knight recommends using a pair of binoculars or a small telescope to try and see the comet. It will be in the northern sky during the evenings, lingering around the constellation Camelopardalis on February 1.

To orient yourself, look to the north and find the Little Dipper (the constellation Ursa Minor). The tip of the Little Dipper’s handle (or Ursa Minor’s tail) is Polaris, the north star. In the early evening of February 1, around 7:30 p.m. ET, the comet will be up and to the right of Polaris by roughly twice the width of your fist at arm’s length. As the evening progresses, the comet’s position will appear to swivel counterclockwise relative to Polaris, along with the rest of the night sky. (For more detailed instructions, Knight recommends consulting skywatching guides.)

Over the first week of February, the comet will appear to move to the east, coming close to Mars on February 10. Not every evening is going to be great for comet viewing, however. During the first week of February, the comet’s position in the night sky will come fairly close to the full moon, which may drown out the comet’s fainter glow for some observers, especially those in areas with high light pollution.

How was this comet found?

C/2022 E3 (ZTF) was found on March 2, 2022, by astronomers Frank Masci and Bryce Bolin. The pair was using the Zwicky Transient Facility (hence the “ZTF”), a wide-field camera at the Palomar Observatory in California that sweeps across the Northern Hemisphere’s night sky every two days, on the lookout for newly appearing objects such as comets and supernovae. When Masci and Bolin spotted C/2022 E3 (ZTF), it was about 399 million miles (643 million km) from the sun, according to Space.com.

The day after it was discovered, Japanese observer Hirohisa Sato saw that the object had a coma, confirming that it was a comet. In the months since, astronomers also have found hints of the comet hiding in archival data, with its first known observation dating to October 25, 2021, according to a database maintained by NASA’s Jet Propulsion Laboratory. (Learn more about the largest comet discovered in modern times.)

(Video) The "Green Comet" Passes by Earth

Wait, back up: we discovered this comet last year?

C/2022 E3 (ZTF) is part of an extraordinary trend over the past 25 years in astronomy. As telescopes have gotten bigger, data have gone digital, and computers have gotten better, astronomers have been able to spot objects in the night sky more easily, revolutionizing the study of asteroids, comets, and other small bodies within the solar system. (Read more about this solar-system revolution in National Geographic magazine.)

The solar system’s farthest reaches hold upwards of a trillion comets, but their orbits are so gigantic and take so long to complete, we can’t see them unless they venture into the inner solar system and reflect enough sunlight our way. Now we can see smaller, dimmer comets at greater distances from the sun than ever before—which means that discoveries are piling up. Only about 3,900 comets have ever been observed formally by astronomers, according to the Jet Propulsion Laboratory database. More than a fifth of them, including C/2022 E3 (ZTF), have been found since 2010.

The Zwicky Transient Facility, which found the new green comet, provides a preview of what to expect from the Vera C. Rubin Observatory, a gigantic facility currently under construction in Chile. Once operational in 2024, it will be the biggest survey telescope ever built, opening up a whole new era of cosmic understanding. Projections estimate that the Rubin Observatory will discover about 10,000 more comets all by itself. “It’s really going to blow things out of the water,” Knight says.

What else does this comet tell us?

C/2022 E3 (ZTF) is also a good sign for what we might learn in future robotic space missions.

The European Space Agency is busy designing a new robotic mission called Comet Interceptor. Once launched in 2029, Comet Interceptor will park itself in the L2 Lagrange point, a gravitational sweet spot a million miles behind Earth from the sun’s point of view, and “hover” there for three years. Its target? Nobody knows yet.

If astronomers discover an incoming object that Comet Interceptor can get to with enough notice—ideally a pristine comet that’s nearing the sun for the very first time—scientists will scramble the spacecraft and plot out a reconnaissance flyby. In doing so, they would get an unprecedented glimpse at the surface of a primordial leftover of the solar system, largely untouched by the sun’s heat and glare.

(Video) What Is A Green Comet, And Why Is It Passing Earth?

According to Knight, who is working on Comet Interceptor, C/2022 E3 (ZTF) is the first comet found since June 2019—when Comet Interceptor was formally selected—that the spacecraft could have theoretically reached. That’s promising for Comet Interceptor, as well as for the future of robotic space exploration.


How can I see the green comet today? ›

Knight recommends using a pair of binoculars or a small telescope to try and see the comet. It will be in the northern sky during the evenings, lingering around the constellation Camelopardalis on February 1. To orient yourself, look to the north and find the Little Dipper (the constellation Ursa Minor).

Has the Green comet passed Earth yet? ›

A recently discovered green comet passed Earth for the first time in 50,000 years.

When can I see green comet 2023? ›

How To See Green Comet in India 2023. In India, the comet should be in the most visible position in the southwestern sky in the early morning hours of June 15th, 2023.

What time can we see the Green comet? ›

The comet should be visible between 10pm and midnight. “The best rule of thumb is to look towards the north,” Webb said.

What comet is visible now 2022? ›

Comet C/2022 E3 (ZTF) is visible for most of the night. While its moving gradually through the night sky the background stars will move more quickly, so its relative position to you will change throughout the night. However, the comet is almost now at the zenith—directly above your head.

Can you see the Green comet in California? ›

SAN DIEGO — On February 1, a rare green comet discovered right here in San Diego will be in its brightest form as it nears earth. If you're in the city, you'll be able to see it using a telescope. But, if you head to our local mountains or desert areas, there's a good chance you can view it with the naked eye.

Did anyone see the Green comet? ›

LUCKNOW: Astronomers and sky gazers of the city were on cloud nine when they spotted the Green comet for the first time on Thursday. Though the view was not very clear, but the sight of the comet that was last seen during Neanderthal age 50,000 years ago filled astronomers with joy.

Where to see the Green comet in oklahoma? ›

OKC Astronomy Club setting up telescopes at Windsurfer's Point to watch comet pass. OKLAHOMA CITY (KOKH) — The Oklahoma City Astronomy Club will be setting up telescopes at Windsurfer's Point on the northeast corner of Lake Hefner to view Comet C/2022 E3 (ZTF).

Can I still see the green comet on feb 3? ›

The Moon shines bright as the green comet C/2022 E3 (ZTF) continues to delight from February 3 to 10.

Can you see the green comet feb 3? ›

Comet ZTF is only observable through moonlight for part of this week, but have a look with binoculars or a telescope anyway! It's very high overhead right after dark now. On February 3rd it should still be near at its peak brightness of about magnitude 5.0.

Will a comet hit Earth? ›

NASA knows of no asteroid or comet currently on a collision course with Earth, so the probability of a major collision is quite small. In fact, as best as we can tell, no large object is likely to strike the Earth any time in the next several hundred years.

Where to see the Green comet chicago? ›

Tune in to the Adler's Sky Observers Hangout at 9 p.m., live from the Doane Observatory. It's a once-in-a-lifetime opportunity to catch a glimpse of the faint, fuzzy smear of light that hasn't been seen in 50,000 years and quite possibly may never come around again.

Can I see the Green comet with the naked eye? ›

That means it will be visible to the naked eye. In fact, the green comet has already been reported to be brighter than +6, with some comet-spotters reportedly seeing it with the naked eye from places with very dark skies ahead of its closest approach. The comet looks like a faint green blob or smudge in the sky.

Is there a comet tonight 2023? ›

Comet C/2022 E3 (ZTF) passes closest to Earth on Feb. 2, 2023.

Can humans land on a comet? ›

Astronauts could indeed land on a comet, however with low gravity and traveling at immense speeds, doing so would be very difficult. Most comets tear through space at incredible speeds; typically many tens of thousands of miles an hour.

Will comet K2 be visible? ›

First, you'll want to be under southern skies. Next, find a dark-sky site. Then, use binoculars or a small telescope to track down the comet. You should see comet K2 as a fuzzy patch of light.

When was hella comet last seen? ›

Astronomers have now linked the comet's appearances to observations dating back more than 2,000 years. Halley was last seen in Earth's skies in 1986 and was met in space by an international fleet of spacecraft. It will return in 2061 on its regular 76-year journey around the Sun.

What planets are visible in Oklahoma right now? ›

Night Sky Bright Planets for Oklahoma City, OK
Mercury6:05 A.M. SE4:00 P.M. SW
Venus8:46 A.M. E7:58 P.M. W
Mars12:51 P.M. NE3:32 A.M. NW
Jupiter9:55 A.M. E10:07 P.M. W
5 more rows

Where is the green comet feb 3? ›

"If C/2022 E3 has ever passed through the solar system before, it would have last been seen in the sky more than 10,000 years ago." "You can find the comet by looking south of the Big Dipper, near the constellation Camelopardalis. If you can find the North Star, you can then trace directly south of that to that."

Can we see Comet Leonard today? ›

Comet Leonard (C/2021 A1) is currently in the constellation of Ophiucus. The current Right Ascension is 17h 20m 34s and the Declination is -19° 19' 15”.

Where to see the green comet in oklahoma? ›

OKC Astronomy Club setting up telescopes at Windsurfer's Point to watch comet pass. OKLAHOMA CITY (KOKH) — The Oklahoma City Astronomy Club will be setting up telescopes at Windsurfer's Point on the northeast corner of Lake Hefner to view Comet C/2022 E3 (ZTF).

How can I see the asteroid 7482? ›

Asteroid 7482 is over half a mile wide, but will thankfully pass Earth from about 1.2 million miles away. You can view the space rock through a six-inch telescope, or check out a livestream of the event.

What day will Comet Leonard be visible? ›

Comet C/2021 A1 — a.k.a. Comet Leonard — will be visible for a little bit longer through mid-January. It flew past Earth at a distance of about 35 million kilometers (22 million miles) on Dec. 12, and made its closest approach to the Sun on Jan. 3.

What time is best to see Comet Leonard? ›

To find it, look east one to two hours before sunrise. It will climb highest in the sky right before dawn, but the sky will also be lightest at that time. Below is a telescope finder chart that shows the path of fast-moving Comet Leonard in the morning sky until December 12.

What time is Comet Leonard coming? ›

"The comet is in the early morning sky right at the moment, and that means getting up very early, probably around 5 a.m. or so and looking more or less to the northeast," Ed Krupp, an astronomer and the director of the Griffith Observatory in Los Angeles, tells NPR.

Will an asteroid hit Earth in 2022? ›

It has since been confirmed that 2022 AE1 will not impact Earth and has been removed from ESA's risk list.

What time will asteroid 7482 Pass Earth? ›

The NASA Center for Near Earth Objects estimates asteroid 7482 will pass within 1.2 million miles of Earth at 47,344 miles per hour at 4:51 p.m. EST.

What asteroid is close to Earth 2022? ›

The largest asteroid to pass within 1 LD of Earth in 2022 was 2022 TM2 with an estimated diameter of around 39 meters for an absolute magnitude of 25.2. The fastest asteroid to pass within 1 LD of Earth in 2022 was 2022 YW6 that passed Earth with a velocity with respect to Earth of 29.8 km/s (67,000 mph).


1. Green Comet to pass over Earth for first time in 50,000 years
2. Green comet to pass Earth for first time in 50,000 years
(Arirang News)
3. Green Comet is Passing Earth for the 1st Time in 50,000 Years
(Inside Edition)
4. What to expect when a green comet visits Earth
5. How to spot Comet C/2022 E3 (ZTF) tonight
(WFLA News Channel 8)
6. NASA: Rare green comet to come close to Earth in rare event
(FOX 10 Phoenix)
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