Illustration by David Foldvari.

Last Monday the International Panel on Planet-Threatening Demi-Gods presented the most peer-reviewed scientific paper in all human history, giving unarguable evidence that Earth will be destroyed by a malevolent super-being called Malignos at teatime (GMT) next Tuesday. I was on tour, sitting in Belfast airport departure lounge, when I read about it in the Guardian. It seemed like an important story, but I noticed other passengers skipping it in their papers in favour, for example, of a charming Daily Mail centre-spread of Photo-shopped pictures of tiny people in a world made of massive vegetables. There was some giant broccoli that a bike had crashed into and a little white man was standing next to it looking at the buckled wheel, scratching his head in astonishment. He simply couldn't believe it. He had driven his bike straight into some giant broccoli!

Malignos the Titan, according to the scientists' report, was four times the size of the Earth, and wore pink Speedos, purple motorcycle boots, and a lilac headdress, similar to Princess Beatrice's royal wedding hat, but almost infinitely larger. Apparently, the hungry space god has been drifting towards the Earth since the early 70s, in full view of astronomers, while shouting: "Resistance is useless. I will drain your planet of all air, water and minerals in an instant. Then everything will die." Scientists and politicians admit that they had some initial difficulty in comprehending the scale and seriousness of the threat. They weren't alone. I nudged the young woman next to me on the departure lounge sofa and showed her a photo of the giant evil god drifting past Mars, and the headline explaining that the world would be destroyed on Tuesday. She pursed her lips, tutted at it, and went back to reading an autobiography of David Walliams.

A big screen in the lounge was showing Lorraine Kelly's ITV morning show. The producers were looking for the fun showbiz angle on the story of the forthcoming destruction of the planet. Varg Vikernes, of the Norwegian Black Metal band Burzum, was among the celebrities already expressing disappointment in their online blogs about the sudden end of all life. Lorraine had a link-up to him deep in the ancient Scandinavian forest, wherein he dwelt.

"I had hoped human civilisation would grind inexorably to a halt in violent disputes over land and resources," Varg told Lorraine Kelly, his white painted face glowing in the primordial gloom, "plunging us back into a second dark age, pitting man against man, race against race, in a barbaric struggle for survival. This sudden end of everything, instantly, has no dignity to it, no nobility. We have been cheated of glory, betrayed by God." And Varg disappeared back into the womb-dark of Mother Forest.

Then Lorraine turned to her studio guest, the transvestite Irish comedian Brendan O'Carroll, titular star of the award-winning Mrs Brown's Boys, who said that the imminent end of everything was "… a fecking shitty thing to happen, and no mistake". People in the departure lounge laughed at the "fecking" bit. I don't think they were really listening to what Brendan and Lorraine were talking about. O'Carroll went on to mention his tour dates, but Lorraine said there would be little point trying to attend them as the world was certain to be destroyed on Tuesday. And they were all sold out anyway.

I flipped the channel to News 24. In an effort to maintain balance, the BBC had finally found someone to dismiss the threat of Malignos the space titan. Appearing live from Oodnadata in the outback, where he was presenting an abandoned upturned tin bath to local people as a reward for good behaviour, Tony Abbott, leader of the Australians, said: "This space-god looks like a poofter to me in his nancy boy hat and shirt-lifter's boots. Send him down here and we'll kick his arse into the back of next week." An Australian tourist on one of the seats behind me applauded and laughed. "Go Tony! Legend!"

I flipped again. On CNN a female news anchor was playing Sarah Palin footage of Malignos, and explaining the god's intent to destroy our planet. Palin laughed, shook her head and said, "There's only one god, ma'am, and I'm pretty sure he doesn't wear Princess Beatrice's royal wedding hat." I'm not a religious man any more, but I went to find the airport's multi-faith prayer room, suddenly moved to address the god I grew up with. But there seemed to be some argument going on in there about whose turn it was to use the prayer mat, and about which religion's prayers were going to be most effective in the light of the current crisis. I went to the bar instead and started drinking.

Later, as I walked back towards the departure lounge, I looked at all the books on the shelves of WH Smith, the classics in a little cluster near the floor. Hardy, Dickens, Eliot, Brontë. It seems trivial I suppose, but it suddenly struck me that all this would be lost too, our finest thoughts, our noblest artistic endeavours. Then I saw a new Jeremy Clarkson book, A Life of Certainty, at the top of the bestsellers' shelves. Perhaps we are getting what we have deserved all along. We are scum. We can't even save the rhino from extinction, and the very thing we're killing him for, his supposedly magical horn, has no medicinal value whatsoever. Come Malignos, come, I found myself thinking, come now, and purify this filthy sphere in space.

Back on News 24 the forthcoming end of the world was already being bumped down the top stories list. A paper that used to be run by Nazi sympathisers had said some bloke's dad was once a communist. The father of a famous lady's son wasn't who we had thought it was. A woman politician had nice shoes. Then Owen Paterson, the environment secretary, came on, to voice his opinion on the IPPTDG's confirmation of Tuesday's apocalypse. "People get very emotional about this subject," he said, "but remember that for humans, the biggest cause of death is cold in winter, far bigger than sudden mass extinction due to the planet-eating ambitions of a world-destroying demi-god. I actually see this report as something we need to take seriously but what it is saying is something we can adapt to over time and we are very good as a race at adapting." I stood up and started shouting: "We're fucked. We're absolutely fucked." "Sit down and be quiet sir," said a member of staff, "you're upsetting everyone."

Stewart Lee is currently on tour with his new stand-up show, Much A-Stew About Nothing. See www.stewartlee.co.uk for details.