A new comet was discovered less than two weeks ago by Hideo Nishimura of Kakegawa, Japan. He was just taking images of the night sky when he discovered it, and now it may become visible to the naked eye in one month.
The comet is currently just outside the orbit of Venus and is visible only through 6″ or greater telescopes with a magnitude of 8.5. That will change over the coming days as the comet screams toward its close encounter with our Sun.
There are a lot of unknowns about the potential visibility of this comet, but currently, it does appear to have a chance to become naked eye visible during September.
Since we have only been observing it for a week, we really don’t know a ton about it. It appears to have an orbit that will sling it out of the solar system after it reaches perihelion, its closest approach to the sun, on September 17, but it may just be several hundred years out and back as well. If it has visited the inner solar system before, that is good news for any potential observers. The comet will come only 20 million miles from the sun (compared to Earth’s 93 million miles), a trip that often causes comets to explode or evaporate completely. If it has survived before, it may do so again.
In the coming days and into the first of September, the comet will be visible in the morning sky. By September 10, the comet will be visible around 45 minutes before sunrise on the east/northeast horizon. By September 13, the comet will have made its closest approach to Earth and transition to an evening object. However, after that, the comet will get very close to the sun from our vantage point. This will make it difficult to pick out even though it may become briefly very, very bright during its closest approach to the sun on September 17.
If, and that is a big if, the comet survives the trip inside Mercury’s orbit, it may become visible again for a few days, but it will remain close to the horizon before eventually becoming completely unobservable by mid-October.
So… while you may hear a lot about this comet in the coming days/weeks ahead, a lot of unknowns remain, and while it may become visible, there are a lot of things that can go wrong. With a little luck, this may be a good appetizer for the next potentially bright comet due in September 2024. I’ve included a couple of maps below of where to find Nishimura courtesy of Stellarium, a free mobile app that I highly recommend downloading.
Stay tuned for more information as we observe the comet longer, and keep your fingers crossed!
