Wake up, step outside in the predawn hours, and take your chance on seeing newly-discovered Comet Nishimura. You might witness something spectacularly fleeting.
Nishimura is named after amateur astronomer Hideo Nishimura, who discovered it just last month while taking 30-second exposures of the night sky with a digital camera. Comet Nishimura is a visitor from the Oort Cloud, a distant and frigid region of the Solar System. If Comet Nishimura ever traveled towards the Sun in the past, that would have been hundreds of years ago. But what makes the vibrant comet’s arrival even more special is that there’s always the risk this could be its last. Its cradle far away from the Sun means it’s made of icy material that could easily break apart as it approaches the star.
For now, it’s still holding together, and skygazers in the northern hemisphere have the best chance to see the comet on Tuesday, September 12. Southern sky observers might even get a bit longer to view the comet, until the start of October, depending on how it fares.
The comet was discovered just under a month ago by Japanese amateur astronomer Hideo Nishimura using a Canon digital SLR camera with a 200-mm lense. Comet sizes are hard to gauge due to the amount of material they expel. The BBC reports that the comet is “a few hundred metres to a mile or two across,” while the Associated Press and USA Today report it to be about a half-mile in size.
How can I view Comet Nishimura?
This visitor will require viewers to wake up early, because it's traveling in an angular direction as it approaches the Sun.
“As the days pass it will become brighter but also lower to the horizon,” according to The Planetary Society, a non-profit science outreach organization. Comet Nishimura will be just 78 million miles (about 1/3rd the distance to Mars at various points) from Earth on September 12.
The Planetary Society also offers some advice on how to spot the comet. “Observers on Earth can see Comet Nishimura with a telescope or binoculars, but may also be able to see it with the naked eye as it grows brighter throughout early September,” the society writes. “Look for it low to the horizon in the predawn eastern sky, rising between the constellations Cancer and Leo and coming close to Venus.”
On September 18, just six days after reaching its closest point to Earth, the comet reaches perihelion. This critical stage brings Comet Nishimura to its shortest distance to the Sun.
If it’s destined to break apart then, September 13 is the last time observers can see Comet Nishimura. But if it survives the stellar rendezvous, observers in the southern hemisphere will see it very low in the western sky at dusk through the end of September, according to The Planetary Society.
The next several days could be the one and only time to see this icy visitor from distant outer space.
