Hideo Nishimura, a photographer from Kakegawa, Japan, has made a significant discovery in the night sky. On August 11 and 12, 2023, Nishimura captured images of a new comet, which has now been named Comet C/2023 P1 Nishimura. Currently located in front of the constellation Gemini the Twins, low in the dawn sky, the comet was previously hidden in the sun’s glare before Nishimura spotted it in his photographs.
Experts estimate that the comet may become bright enough to see without optical aid, but caution that it will be challenging to locate against the glare of the sun or daylight. However, there are still opportunities to observe the celestial visitor using binoculars, a small telescope, or long-exposure photos in the last days of August and the first days of September. Additionally, there is hope for an outburst while the comet is still distant from the sun.
The current observed magnitude of the comet is around 9.2, meaning that individuals using telescopes in a dark sky can already spot it. Reports indicate that the comet’s tail is eight arcminutes long, and as it nears the sun, it is expected to continue brightening and the tail to grow. The comet will reach its brightest point in September when it is closest to the sun and Earth.
By August 15-16, 2023, Comet Nishimura had already passed Earth’s orbit as it continues its journey toward the sun. The comet is traveling at such a rapid pace that it will reach Venus’ orbit by August 27, 2023. Sky enthusiasts are encouraged to observe the comet with a small telescope during the remaining days of August.
The path of Comet Nishimura is still being defined due to limited observations. NASA/JPL recently made new orbital calculations, indicating that the comet orbits the sun every 202 years, suggesting it is a “local” comet from our solar system rather than an interstellar comet. The closest approach to Earth will occur on September 12, 2023, when the comet will pass at a distance of 78 million miles (125 million km). Its closest approach to the sun, known as perihelion, will take place on September 17, 2023, passing only 27 million miles (43.7 million km) from our star.
Estimating a comet’s brightness is challenging due to their unpredictable nature. Comet Nishimura could be bright enough to see with the unaided eye, but there is also a possibility of it disintegrating as it nears the sun. Approximations suggest that the comet will be magnitude 4.9, within range of the unaided eye, on September 11. It will be visible near the crescent moon, Venus, and the star Adhafera in Leo’s Sickle. However, the bright sunlight coming from below the horizon may make spotting anything in the sky extremely challenging.
As the comet moves away from the sun, it will start to fade in brightness. By mid-October, it will be farther from the sun in our sky but becoming dimmer. It will also spend most of its time in daylight or below the horizon.
Overall, Comet Nishimura provides a unique opportunity for sky enthusiasts to observe a new celestial visitor.