CAPE CANAVERAL, Fla. (AP) — A comet is returning to our path after 50,000 years.
The dirty snowball was last visited during Neanderthal times, according to NASA. It will come within 26 million miles (42 million kilometers) of Earth on Wednesday before moving away again, and is unlikely to return for millions of years.
So look up, contrary to the title of the killer comet film “Don’t Look Up”.
Discovered less than a year ago, this harmless green comet is already visible in the northern night sky with binoculars and small telescopes, and possibly with the naked eye in the darker corners of the hemisphere. north.
It is expected to brighten as it nears and rise higher on the horizon until late January, best seen before dawn. On February 10, it will be close to Mars, a good point of reference. Southern hemisphere skygazers will have to wait until next month to get a glimpse.
While many comets have graced the skies over the past year, “this one probably looks a little bigger and therefore a little brighter and it’s getting a little bit closer to Earth’s orbit,” the report said. NASA comet and asteroid tracking guru Paul Chodas.
Green from all the carbon in the gas cloud, or coma, surrounding the nucleus, this long-period comet was discovered last March by astronomers using the Zwicky Transient Facility, a wide-field camera at Caltech’s Palomar Observatory. .
This explains its official and cumbersome name: comet C/2022 E3 (ZTF).
On Wednesday, it will rush between the orbits of Earth and Mars at a relative speed of 128,500 mph (207,000 kilometers). Its core is thought to be about a mile (1.6 kilometers) in diameter, with its tails extending for millions of miles (kilometers).
The Comet isn’t expected to be as bright as Neowise in 2020, or Hale-Bopp and Hyakutake in the mid to late 1990s.
But “it will be bright because of its close passage to Earth … which allows scientists to do more experiments and the public to be able to see a beautiful comet,” said University of Hawaii astronomer Karen Meech, in an email.
Scientists are confident in their orbital calculations placing the comet’s last pass in the planetary neighborhood of the solar system 50,000 years ago.
But they don’t know how far it came from Earth or if it was even visible to Neanderthals, said Chodas, director of the Center for Near Earth Object Studies at NASA’s Jet Propulsion Laboratory in California.
When he returns, however, it’s harder to judge.
Each time the comet orbits the sun and planets, their gravitational tugs very slightly alter the trajectory of the ice ball, causing major course changes over time. Another joker: jets of dust and gas from the comet as it heats up near the sun.
“We don’t know exactly how far they’re pushing this comet,” Chodas said.
The comet – a time capsule of the solar system emerging 4.5 billion years ago – came from what is called the Oort cloud far beyond Pluto. This freezing paradise for comets is thought to stretch more than a quarter of the way to the next star.
Although Comet ZTF originated in our solar system, we can’t be sure it will stay there, Chodas said. If it is expelled from the solar system, it will never return, he added.
Don’t worry if you miss it.
“In the comet realm, you just wait for the next one because there are dozens of them,” Chodas said. “And the next might be bigger, might be brighter, might be closer.”
The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute Science and Education Media Group. The AP is solely responsible for all content.
