Stargazers in California saw the newly-discovered comet C/2023 A3 lighting up the sky.
Just days after the northern lights illuminated the sky over New Jersey, the Garden State may be in for another show from space as a comet is expected to be visible throughout the rest of October, and another comet may be on its way.
"Earlier this year we got a look at Comet 12P, which was visible with binoculars but not super bright," said NASA's October 2024 Sky Watching Tips. "Now another one of these ancient and icy dust balls is streaking through our neighborhood on an 80,000-year orbit from the distant reaches of the Oort Cloud."
This comet could become the brightest of the year, according to NASA.
The comet, known as C/2023 A3, also known as Tsuchinshan-ATLAS, passed its closest to the sun on Sept. 27.
On Oct. 12, it was expected to be within 44 million miles of Earth, becoming visible primarily to those in the Southern Hemisphere and the tropics until about Oct. 8, according to NASA's Earth Observatory. Those in the Northern Hemisphere will have the opportunity to view the comet throughout the rest of the month.
Astronaut Don Pettit, who is currently aboard the International Space Station, captured a photo of Tsuchinshan-ATLAS on Sept. 19 as it approached the sun. The crew aboard the station have been observing the comet throughout its journey through the inner solar system.
According to Smithsonian Magazine, Tsuchinshan-ATLAS was first spotted in early 2023 by the Purple Mountain Observatory in China. Soon after its discovery, the comet disappeared and was presumed lost.
However, a month later, the celestial object was rediscovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in South Africa and confirmed to be a comet.
The comet was named Tsuchinshan-ATLAS after both observatories as "Tsuchinshan" means "purple mountain" in Mandarin, according to Smithsonian Magazine.
When is the best time to view the comet?
According to NASA, Tsuchinshan-ATLAS will become visible low in the west following sunset between Oct. 14 and Oct. 31.
It will rise higher each evening, making it easier to observe, but will also get a little bit fainter each night. The comet may be visible to the naked eye if its tail is well-illuminated by sunlight.
The first week and a half, between Oct. 14 and Oct. 24, will be the best time to observe the comet using binoculars or a small telescope, and a "reasonably clear view toward the west," said NASA.
C/2024 S1 (ATLAS)
Another comet, known as C/2024 S1 (ATLAS) was discovered by ATLAS at the end of September and is expected to be visible in late October or early November, according to Smithsonian Magazine.
Per Smithsonian, the comet is called a "sungrazer" because it is part of the Kreutz group, a family of comets that fly exceptionally close to the sun. Due to this, they either glow brightly or disintegrate.
"While expectations are high, stargazers shouldn't be shocked if either (or both) comets ultimately underperform," said Smithsonian Magazine. "But astronomers will be keeping their eyes on the skies to see if one of these celestial bodies becomes the comet of the century."
What is a comet?
According to NASA, comets are "frozen leftovers from the formation of the solar system composed of dust, rock and ices" that orbit the sun.
As a comet's orbit brings it close to the sun, it heats up, spewing dust and gases into a glowing head that is "larger than most planets." The dust and gases then form a tail that stretches for millions of miles away from the sun.
Per NASA, there are likely billions of comets orbiting our sun in the Kuiper Belt and the Oort Cloud, which is a "large, spherical shell of icy debris at the outer reaches of our solar system."
Both of the incoming comets likely originated in the Oort Cloud, according to NASA, as they have extremely long orbits.