A comet which NASA deemed would be the "brightest for a century" could break up and evaporate before we get the chance to see it. 

Comet Ison is due to graze the surface of the sun on Thursday November 28th and astronomers are hoping it will put on a dazzling display from then until the middle of January.

Now Josh Barker of the UK's National Space Centre has said the sun threatens to destroy Ison with its gravitational pull and solar energy.

"It could be the comet of the century. If all goes to plan, if all the little pieces line up just properly, we could have one of the brightest comets that we've seen certainly in current human life and one of the brightest in history, so it could potentially be very exciting, although there's a lot of margin for error."

The break-up of the comet would pose no threat to Earth, because the fragments would continue to follow the same trajectory.

The comet is believed to be several kilometres in diameter and will be travelling at around 1.36 million kilometres per hour as it passes within 1.17 million kilometres of the sun's surface.

Rays from the sun will heat the ice, metal and rock to 2,760 degrees Celcius.

Ison was discovered on September 21st, 2012 by Vitali Nevski and Artyom Novichonok, two Russian astronomers of the International Scientific Optical Network (Ison).