Looking into comet Tsuchinshan-ATLAS, its origins

ROCHESTER, Minn. (KTTC) – The Tsuchinshan-ATLAS comet, or C/2023 A3, has caught the interest of millions in the northern hemisphere since Saturday, Oct.12 and formed more than four billion years ago.

Michael Rutkowski, Associate Professor in Physics and Astronomy at Minnesota State University Mankato, said this comet is a chance for scientists to study what he describes as 'the perfect time capsule' of the early solar system.

"Scientists get really excited about comets..." he said. "You can't go into the Earth and find rock that's 4.5 billion years old because it's been processed multiple times, or it's been taken into the deep interior of the earth and ejected back out then chemically modified."

The Tsuchinshan-ATLAS comet was created more than 4 billion years ago when the planets reshuffled and changed the gravitational field in our solar system, according to Rutkowski.

"They [comets] formed really close into the sun, I mean much closer than they are now...," he said. "When the planets migrated outwards early in the history of the solar system that ejected a bunch of stuff, a bunch of icy material and it ejected it to huge distances."

The icy material that was sent out to the outer regions of the solar system is known as the Oort Cloud. The cloud is also made out of space debris and is 5,000 to 10,000 astronomical units (AU) away from the sun, according to NASA.

"The mean distance between the Earth and sun, is an astronomical unit," Rutkowski said. "Once you are out at 1,000 AU or 10,000 AU then you are in the Oort Cloud region.

The equivalent of one astronomical unit is 93 million miles , according to NASA. The Tsuchinshan-ATLAS comet is a long period comet and comes from the cloud. Kelly Bahl, Naturalist at the Jay C Hormel Nature Center, said short term comets, like Haylee's Comet, originate from the Kuiper Belt. The Kuiper Belt is a region that is found between Neptune and Pluto.

"Our short-term comets that we get to see more often like the famous Haylee's Comet, that comes from the Kuiper Belt because that has a smaller orbit around the sun," she said. "Those ones [long term comets] that are so far away by the time they make it back here it will be tens of thousands of years, whereas the ones from the Kuiper Belt it could be 50 years or 100 years or something much more manageable time wise."

The Atlas comet will soon be difficult to see with the naked eye as it gets farther away from the sun based on its trajectory.

"The distance it has from the sun now we wait until after the sun sets, we see it higher in the sky every single night as it gets further and further away from the sun," Bahl said. "So, as it gets further away it is going to get higher in the sky, but it is also going to get a little dimmer."

Viewing conditions are expected to decrease throughout the next few nights but should be still viewable through Oct. 24 through binoculars and telescopes, according to NASA . The government agency also said the trajectory of the Tsuchinshan-ATLAS comet is expected to leave the solar system.