An incredibly rare phenomenon
A once in a life time event is about to happen this weekend, providing human’s on earth today with a spatial time capsule last seen by our Neanderthal ancestors 80,000 years ago.
The event in question concerns the comet known as C/2023 A3 Tsuchinshan–ATLAS, or A3 for short, and its encounters with Earth are so rare that the last time it passed humans as we know them did not exist.
The comet in question is such an infrequent visitor to Earth that its orbital period counts 80,000 years. For reference the Earth’s orbital period is one year, around the sun.
However, you’ll want to make sure you catch a glimpse of this one as, if you miss it, the comet won’t be back for another 80,000 years – probably a bit too long to outlive.
Since the 27 September, the comet has been visible in the Southern Hemisphere, but as we get into October the comet will become visible in the Northern Hemisphere.
This Saturday, the comet will fly past Earth at about 44 million miles away which, for reference, is quite close when you consider Mars is 38.6 million miles from Earth at its closest point.
The weekend’s flyby will be the first documented passing of the ancient celestial object and would have last been seen by our long lost ancestors the Neanderthals.
The comet will reportedly look like a bright fireball in the dark sky with a trailing tail.
Speaking to CNN, Bill Cooke, lead of NASA’s Meteoroid Environment Office at the Marshall Space Flight Center in Huntsville, Alabama, recommended taking binoculars to watch the comet..
He said: “It’s not going to zing across the sky like a meteor. It will just appear to hang there, and it will slowly change position from night to night,” Cooke said. “If you can see (the comet) with your unaided eye, (using) the binoculars will knock your socks off.”
For those in the UK the comet is expected to be visible from Saturday 12 October in the west of the night sky and should be visible until 30 October.
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EarthSky have reported that the best days to see the spectacle will be between 14 October and 24 October.
As with any celestial event, the best way to view the comet will be around midnight when the sky is at its darkest away from population centres and clear skies are crucial.
A comet is a large ball of frozen gas, rock and dust that orbits the sun.
Meanwhile meteors come from debris that is shed from comets that then hit the earth’s atmosphere expulsing bright streaks of light as the friction burns up the particles high in the sky.
A meteor is a meteoroid that burns up in the Earth’s atmosphere while a meteorite is a meteoroid that reaches the Earths surface.
Meteoroids are typically 2mm to 1m in size while an asteroid is anything larger.
Comets have bright burning tails because as they get closer to the sun, its heat vaporises some of its ice and dust releasing gases that are pushed away by solar radiation and wind forming tails that can reach up to hundreds of kilometres long.