This week, a rare green comet will be visible to the naked eye above Ireland. It will be at its brightest on February 1 and 2.
Since the time of the Neanderthals, the comet, also known as Comet C/2022 E3 or ZTF, hasn’t been visible from Earth. It only orbits the sun once every 50,000 years.
ZTF, which gets its name from the Californian Zwicky Transient Facility, was only recently discovered in last March.
The comet, which originates from the Oort cloud at the edge of the solar system, will pass close to Earth when it is 43 million kilometres away, or about one-third of the distance between Earth and the sun.
The comet will be at its brightest next Wednesday and Thursday, the first two days of February, David Moore, the founder of Astronomy Ireland, told The Journal.
“I’ve seen it in binoculars, some keen-sighted people in the countryside say they can faintly see it with the naked eye already, which makes it one of the brightest comets of the last few years,” he said.
Tonight is forecast to be cloudy, which may make the comet tough to spot, especially as it remains so far from Earth.
However, clouds aren’t the biggest obstacle when it comes to spotting the comet with the naked eye, Moore explained.
“It was clear last night and it wasn’t supposed to. That’s the Irish weather, even if the forecast is bad, check anyway,” he said.
“Today, we’re our own worst enemy. We’re polluting the oceans with plastic, the atmosphere with carbon dioxide and methane but also the nice dark night’s sky with artificial light that blocks out stars and comets.”
People in cities and large towns will struggle to get a view of the comet even when it gets its closest to Earth.
“Get away from streetlights,” Moore advised.
“That’s the best thing you can do to increase your odds of a good view. We are lucky because the comet will be near the North Star. It will be visible from dusk to dawn so you don’t have to perfectly time you viewing. Ireland has a ringside seat.”
The comet will be much easier to see through binoculars or a telescope, and Astronomy Ireland will host a viewing tomorrow at its headquarters close to Blanchardstown to let members of the public use its large telescope.
“The great thing about astronomy is that even though this comet wasn’t visible since the Stone Age, 50,000 years is nothing in the timescale of astronomy.”