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A bright-green comet not seen since last ice age will be in D-FW skies this month

Dallas Morning NewsDallas scientists say the comet takes 50,000 years to make a trip around the sun.

A bright-green comet that has not been seen since the last ice age will be visible in D-FW skies later this month.

The comet, called C/2022 E3 (ZTF), was discovered by astronomers at the Zwicky Transient Facility in March 2022. According to NASA, it will be visible in the Earth’s Northern Hemisphere, including D-FW, in January, and the Southern Hemisphere in February.

Comets can take anywhere from hundreds to millions of years to complete an orbit around the sun. The well-known Halley’s Comet takes about 76 years. This bright-green comet takes 50,000 years to make the trip.

“The last time it was close to Earth was about 50,000 years ago, which was really at the time when Homo sapiens, our species, just started to emerge,” said Manfred Cuntz, a physics professor at the University of Texas at Arlington.

What are comets?

Comets are like “messengers from the super-early solar system,” Cuntz said. Scientists study them to gain information about the materials used to create our solar system.

They’re made of rock, ice and frozen gases. Comets heat up when they approach the sun, releasing gas and dust and forming their characteristic tails.

This comet’s bright-green color may be caused by a type of gas that is boiling off it, said Matt Siegler, an adjunct professor at Southern Methodist University.

He added that this comet’s long orbit makes it a marker of human history.

“A lot has happened to humans in the past 50,000 years,” said Siegler, who is also a research scientist at the nonprofit Planetary Science Institute. “And it’s neat to think that the last people who saw this were living in such a different world.”

How can I see this bright-green comet?

According to NASA, the comet is “sweeping across” the northern constellation Corona Borealis. It will likely be visible in D-FW skies in mid- to late January, Cuntz said. He recommended checking NASA’s website later this month for the best times to catch a glimpse.

The comet may be visible to the naked eye, and it can definitely be viewed with binoculars or a telescope. Siegler said a telescope app on a mobile device would suffice.

Cuntz recommended looking for the comet during early mornings when the sun is low. He suggested city dwellers move away from artificial city lights for the best sighting.

“This [artificial] kind of light is always competing against light from stars and celestial objects,” he said.

The bright-green comet is like an outer space time capsule: a rare shared moment between the beginnings of humanity, our current generation and the planet’s inhabitants 50,000 years into the future.

As Cuntz said: “It’s literally speaking, a once-in-a-lifetime chance.” READ MORE