Comet Nishimura set to resurface this month after 400 years
A brand-new bright comet will dazzle the sky across the Northern Hemisphere this September.
Stargazers residing in this part of the globe can catch a glimpse of this comet Nishimura in the early hours before dawn on September 12 and then again around September 17 – before it fades into the Sun's brightness.
Comet C/2023 P1 (Nishimura): Such a strong solar wind. The disconnection event on September 2nd - the spectacular development in a 20-minute animation (RASA 11 QHY600) and 4x80sec red Michael Jäger pic.twitter.com/qf43YqhBbl
— Michael Jäger (@Komet123Jager) September 2, 2023
If the comet survives its scorching close encounter with the Sun, it is expected to be visible in the Southern Hemisphere during evening twilight by the end of September.
The discovery of the comet
Reportedly, on August 12, 2023, Hideo Nishimura, an amateur astronomer from Japan’s Kakegawa City, discovered this comet. He took 30-second exposures using a standard Canon DSLR camera with a telephoto lens. Upon processing the exposures, it became evident that there was a luminous object swiftly traversing our inner solar system.
On August 15, the Minor Planet Center formally confirmed the finding and named the comet C/2023 P1 (Nishimura). The letter designation "C" signifies a non-periodic comet, which means these types of comets have their origins in the Oort Cloud and can either make a single pass through the solar system or have orbital periods ranging from 200 to thousands of years before returning to the vicinity of the Sun.
According to the Comet Observation Database (COBS), Nishimura is categorized as a "hyperbolic comet." This categorization suggests that the comet has abundant energy, preventing it from being permanently caught within the solar system.
C/2023 P1 Nishimura 2023 sep. 5 2.30 UT 15min 16"/3.2 Moravian G3-16200 and Leica Apo-Telyt 280/4.0 10x90sec Nikon Z50mod Michael Jäger pic.twitter.com/B0NqccGnWD
— Michael Jäger (@Komet123Jager) September 5, 2023
“It will visit us only once, with the sun acting as a gravitational slingshot, sending the comet hurtling back into deep space after its flyby,” it mentioned.
To depart the solar system, the comet must first survive the Sun's perihelion, the closest point in its orbit to the star.
Survival during the close approach to the Sun
Comets that approach the Sun for the first time are at a greater risk of disintegration, and the fate of Nishimura is highly uncertain.
When the intense sunlight makes contact with the comet's surface for the first time, a wide range of outcomes becomes possible. Due to the heat and pressure produced by the Sun and the solar wind, the comet may melt and disintegrate in some cases.
One such example is the Comet ISON, which disintegrated just a few weeks before it was anticipated to deliver a remarkable celestial display in the sky.
While the brightness of a comet may increase dramatically in some cases, as comets approach the Sun, the heat transforms their frozen core into dust and gas, creating a long tail. Sunlight bounces off its tail, allowing us to see comets from Earth.
Moreover, the images depict greenish-hue, limited to the comet's head, not its tail. This is because the green color in the head comes from diatomic carbon, a reactive molecule formed when sunlight interacts with organic matter on the comet's surface.
On September 18, comet Nishimura will reach its perihelion, or closest approach to the Sun in its orbit. If it can endure the Sun's radiation without breaking up, it will circle and begin its trip back.
Peak show in mid-September
Soon after the announcement of its discovery, comet enthusiasts and astrophotographers from all around the globe began monitoring Nishimura's path, snapping some stunning photographs over the last few weeks.
The coming weeks should particularly offer a better chance to catch a glimpse of this comet. It is now transiting the constellation Leo in the early morning hours before sunrise.
C/2023 P1 (Nishimura) 2023 sep 6 GIF 2.13-44 min 16"/3.2 Moravian G3 16200 Michael Jäger pic.twitter.com/UcoybmjkoE
— Michael Jäger (@Komet123Jager) September 6, 2023
While the best view will be on September 18, when it is expected to appear much brighter with a magnitude of 2.9.
“A problem is that the comet will also be angularly near the Sun, so it will only be possible to see it near sunset or sunrise,” NASA wrote in a blog post.
For the best view, use small binoculars to watch this celestial show.