Comet ATLAS, also known as C/2019 Y4 but nicknamed ATLAS as it was discovered by the telescope array system of the same name, will become increasingly bright. The comet is currently in close proximity to Mars’ orbit, but is heading closer to the Sun.
By late May, it will only be 0.25 AU away from the Sun – one AU (astronomical unit) is equivalent to the distance between the Earth and the Sun – and getting closer.
When it approaches the Sun, it could become as bright as a waxing crescent Moon – the curved lunar phenomenon which is visible at the beginning and end of the Moon’s monthly cycle.
Website Space Weather said: “The comet is about as bright as an 8th or 9th magnitude star. That’s too dim to see with the naked eye but consider this: The comet is hundreds of times brighter than astronomers predicted when it was discovered 4 months ago by the Asteroid Terrestrial-impact Last Alert System (ATLAS). And it’s still beyond the orbit of Mars.
“By the time Comet ATLAS approaches the sun in May, it could become quite bright, indeed.
“Estimates range from magnitude +1 to -10; in other words, somewhere between a 1st magnitude star and the waxing crescent Moon.”
Three weeks ago, amateur astronomer Roman Kulesza of Ontario, Canada, tried to find Comet ATLAS but to no avail.
Mr Kulesza said: “It wasn’t easy. But last night – wow! The comet has really brightened.”
Space Weather added: “Can’t wait for May? Amateur astronomers with mid-size backyard telescopes can observe Comet ATLAS now.
Experts are unsure whether it will burn to dust or whether it will produce a spectacular display of explosions as it approaches the Sun.
Karl Battams of the Naval Research Lab in Washington DC said: “ATLAS is a bit of a wildcard, and there’s a spectrum of possibilities as it nears the sun.
“At one extreme, it could simply crumble away in the coming weeks, and at the other extreme it could brighten up tremendously.
“It has an unusually small perihelion distance inside of Mercury’s orbit, which bodes well for getting those frozen gases fizzing furiously.”