Of all the celestial bodies in our solar system, perhaps the most spectacular are the great comets that occasionally grace our skies. If you have been on social media in recent days, you have probably seen an article declaring that there is such a comet in our sky right now: C/2023 P1 (Nishimura).
As I write this, Comet Nishimura is flying away on its first visit in over 400 years. Japanese astronomer Hideo Nishimura discovered this comet on August 12th. Soon after, pre-discovery images of the comet dating back to January were discovered, allowing astronomers to determine its path.
They quickly realized that Nishimura would swing closer to the Sun than Mercury’s orbit this month. Considering the comet’s brightness at the time of its discovery, it may become bright enough to be seen with the naked eye. So will a wonderful sight appear in our skies? Probably not.
Unfortunately, Nishimura’s path will remain close to the sun in the sky as seen from Earth. It is certainly bright enough to be seen with the naked eye even in a dark sky, but at most it just blends into the horizon just after sunset and is almost completely obscured by the brightness of the sun.
Still, astronomers around the world are excited. Even comets that are difficult to see with the naked eye are worth observing.and as science writer and astronomer David H. Levy I once said: “Comets are like cats. They have tails and they do exactly what they want.”
Related: Is the newly discovered Comet Nishimura really visible to the naked eye?experts aren’t sure
There is also the possibility that Nishimura will unexpectedly brighten up. If that happens, we might see something special in the coming weeks. If not, there’s always next year. But more on that later.
bright comet recipe
In the icy depths of space, far from the Sun, comets essentially become dirty snowballs, chunks of ice, dust, and rock left over from the formation of the Solar System.
As a comet approaches the Sun, its surface begins to heat up. Ice near the surface becomes hotter,majesticThis gas carries dust and debris, covering the core in a transparent cloud of gas and dust called a “coma.”
The solar wind then blows gas and dust away from the Sun, giving the comet a tail.tail everytime Points away from the sun.
The comets we see are sunlight reflected from the gas and dust in the coma and tail. The nucleus itself is not visible. Therefore, the brightness of a comet is usually determined by three factors:
- Nucleus size: A larger nucleus usually means a larger active area (although some comets are more active than others) and more gas and dust production.
- Distance to the Sun: The closer a comet is to the Sun, the more active (and brighter) it becomes.
- Distance to Earth: The closer a comet is to us, the brighter it appears.
What about Mr. Nishimura?
So let’s talk about Comet Nishimura. Nishimura probably doesn’t seem that big – otherwise it would have been discovered much earlier – and it’s not particularly close to Earth either. However, it is passing relatively close to the Sun and is expected to be very active near its perihelion (the point closest to the Sun).
If you could see it in a dark night sky, this comet would be pretty impressive. Sadly, even at his best, Nishimura will end up being closer to the sun in the sky.
What’s more, the comet and Earth just so happen to be in the worst possible orientation for observation. Nishimura will remain close to the sun as it moves away from us, remaining buried in the star’s glare.
A short window to see Nishimura from Australia
Nishimurayama will peek out over the western horizon shortly after sunset, but only briefly. The best chance to see the comet from Australia will come during the week of September 20-27, when the comet’s head will set about an hour after the Sun. It will be furthest from the sun in the evening sky on September 23rd.
As dusk ends, Nishimura is very close to the western horizon and is about to set. This means you can become invisible in the sun’s glare.
But remember that comets are like cats. Some comets break apart when they are closest to the Sun, and when they do, they often become noticeably brighter. If that happened to Nishimura, it might be easier to detect.
Unfortunately, the comets most likely to break up are those that are visiting the inner solar system for the first time and traveling in very long-period orbits of tens or hundreds of thousands of years. Mr. Nishimura is an experienced visitor, with an orbital period of about 430 years. It has likely survived many passes through the sun, so it is less likely to fall apart.
Nevertheless, even though the comet’s head is no longer visible in the twilight, the tail may still be visible as the sky darkens. Before the comet disappeared into the glare of Northern Hemisphere observers, observers saw its tail as long as about 6 degrees, but the tail will likely lengthen as the comet approaches the Sun.
If you’re lucky, you might be able to spot their tails standing proudly above the horizon as the sky darkens.
next big comet
Even if Nishimura doesn’t put on the show he hoped for, there’s a chance that another comet will put on a really great show next year. Comet C/2023 A3 (Tsuchinzan-ATLAS) It was discovered earlier this year. It is currently about the same distance from the Sun as Jupiter.
It will continue descending toward the Sun over the next 12 months, reaching its closest approach to the Sun in late September 2024. Tuchinshan-ATLAS looks promising. If it works as expected, it could be a spectacular sight. But remember: It means that comets resemble cats.
Check out our guides to the best binoculars and best telescopes to find the right telescope for you. If you want to take pictures of Comet Nishimura, or the night sky in general, check out our guide on how to photograph comets, as well as the best cameras and lenses for astrophotography.
Editor’s note: If you have captured an image of Comet Nishimura and would like to share it with Space.com readers, please send your photo, comment, name and location to: spacephotos@space.com.