A comet speeding towards the inner solar system could become one of the brightest objects in the night sky, promising the most dramatic display of its kind in decades.
Astronomers believe that Comet Atlas, which in one month has grown 4,000 times brighter than when it was first spotted, has the potential to become “the comet of a generation” if it maintains its composition.
“It’s definitely a promising comet,” Daniel Brown, an astronomy expert at Nottingham Trent University, said yesterday.
“It’s pushing towards a level that by the end of April could look really, really stunning.”
The comet was discovered by astronomers at the Asteroid Terrestrial-impact Last Alert System (Atlas) at the University of Hawaii, which scans the sky for near-Earth objects and calculates whether they could pose a hazard to our planet.
The comet is not a danger to Earth: it will breeze past at a distance of about 72 million miles. On its way, it could rival Venus, the second brightest object in the night sky after the moon. Comets are clusters of ice, frozen gases and other chemical elements left over from the formation of our solar system 4.6 billion years ago. Experts liken them to dirty snowballs — or even snowy dirtballs. “It’s a mixture of rubble and ice but it can be more snowball than dirt,” Dr Brown said. “As they get closer to the sun they gas off this material and we get this amazing display. It’s already at a level of brightness that you can see through binoculars — this beautiful greenish halo around it and a bit of development of the tail.” Atlas could become visible to the naked eye during the first weeks of April and, if it does not fizzle as it closes in on the sun, will be at its most brilliant by the end of May. Optimism as to its potential is driven by the fact that it is following the orbit of the Great Comet of 1843, which had a tail twice as long as the distance from the Earth to the sun. Comets can be notoriously erratic, however. David Levy, a Canadian astronomer who co-discovered the Shoemaker-Levy 9 comet in 1993, wrote: “Comets are like cats. They have tails and they do whatever they want.” The timing might raise eyebrows for those who believe the theory that historical comets may have contaminated Earth’s atmosphere and triggered devastating terrestrial plagues such as the Black Death in the 14th century.