- Comet Nishimura could grace our skies with its eerie glow in early September.
- The comet may become visible to the naked eye in the coming weeks, NASA said.
- It may be one of the very few interstellar objects that have visited our solar system.
A mysterious green comet, called Comet Nishimura, could be visible to the naked eye in mid-September.
Also known as Comet C/2023 P1, the cosmic object could be more easily visible from September 7 and will reach its peak brightness on September 17 when it will be 78 million miles from Earth.
The comet, which got its name from the Japanese astronomer Hideo Nishimura, currently has a green tail and is gaining in intensity as it heads toward the sun, NASA reported.
This is a crucial stage. The sun can make comets brighter by freeing more gas into their tails. But it can also break them up before they reach the Earth.
Still, NASA is optimistic. "Will Comet Nishimura become visible to the unaided eye? Given the unpredictability of comets, no one can say for sure, but it currently seems like a good bet," NASA said in a blog post.
Backyard astronomers are encouraged to take their telescopes out to spot the comet in case it breaks up in the coming days, comet-tracking app SpaceWalk suggested on its blog.
For the rest of us, it's worth turning our attention to the skies from early September in the hours before dawn. The comet is almost aligned with the sun, so the best chance of catching it is right before our star rises.
This could be a rare interstellar object
Some have suggested the comet's orbit seems hyperbolic, meaning it would have "too much energy to remain inside the solar system."
This would mean the comet has come from interstellar space and is just visiting our solar system before it heads out to outer space forever.
"The comet will only visit us once, with the sun acting as a gravitational slingshot, sending the comet hurtling out of the solar system after its flyby," spaceweather.com reported.
If this hyperbolic orbit is confirmed, Comet Nishimura would join a very short list of interstellar objects that have visited the solar system.
This includes Oumuamua, a bizarre space rock that moved around space in a way that first puzzled scientists and caused some to wrongly speculate it could have been an alien ship.
Others, however, think the comet has come from the source of many other comets, the Oort cloud near the outer reaches of our solar system, Forbes reported.
That would then mean the comet is on a very long orbit around the sun and could visit us again, though probably not for hundreds or thousands of years.
