Green comet, visible in the night sky for first time since Stone Age, makes its closest pass by Earth

By Ashley Strickland and Katie Hunt, CNN

Updated 2329 GMT (0729 HKT) February 2, 2023

Comet C/2022 E3 (ZTF), which last passed by our planet about 50,000 years ago, is seen from the Pico de las Nieves on the island of Gran Canaria, Spain, on Wednesday.
Comet C/2022 E3 (ZTF), which last passed by our planet about 50,000 years ago, is seen from the Pico de las Nieves on the island of Gran Canaria, Spain, on Wednesday.
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.

(CNN)A green-hued comet has made its closest approach to Earth, wowing night sky watchers in the Northern Hemisphere who caught a glimpse of the icy celestial object as it passed through our cosmic neighborhood.

Discovered in March by astronomers using the Zwicky Transient Facility's wide-field survey camera at the Palomar Observatory in San Diego County, California, it was last visible in the night sky during the Stone Age — about 50,000 years ago.
Named C/2022 E3 (ZTF), the comet has an orbit around the sun that passes through the outer reaches of the solar system, which is why it's taken such a long route — and long time — to swing by Earth again, according to The Planetary Society.