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Green Comet Makes an Appearance for the First Time in 50,000 Years

By Jessica Stewart on February 3, 2023

Photo: Alessandro Bianconi via Wikimedia Commons (CC BY-SA 2.0)

An asteroid swung by South America recently to say hello; and not long after, another space object has paid Earth a visit. Comet C/2022 E3 (ZTF) is a green comet that last visited our solar system 50,000 years ago. It was only discovered in March 2022, when it was spotted by the Zwicky Transient Facility (ZTF). Given its long orbit, we're unlikely to ever see it again in our lifetimes.

The comet made its closest approach to Earth on February 1, when it was just 26 million miles away. Even though Comet C/2022 E3 (ZTF) is now traveling away from Earth, it will still be visible for the next few weeks. So how can you see it? Though it could be visible to the naked eye—particularly on a clear night without a lot of light pollution—the comet is more easily spotted using binoculars or a telescope. To orient yourself, Comet C/2022 E3 (ZTF) is predicted to be close to the Capella star in the Auriga constellation on February 5. Another good time to look out for the comet is between February 9 and February 13, when it will appear close to Mars in the Taurus constellation.

While this green comet isn't as bright as Comet Neowise or Comet Leonard, it's still making quite a splash. Astrophotographers, including one of our favorites Andrew McCarthy, are enjoying the opportunity to document the rare sighting. Last visible during the Paleolithic era, comet C/2022 E3 (ZTF) is an incredible connection to the past and reminds us of just how long the history of the universe truly is.