A Muswell Hill astronomer and his students made a serendipitous discovery when they spotted a dazzling supernova during a break in recent bad weather.

Dr Steve Fossey, of Alexandra Road, was teaching his weekly class at the UCL Observatory, in Watford Way, Mill Hill, when he caught a glimpse of the cosmic blast in a galaxy 12million light years away.

Since the dramatic find, Dr Fossey and his star students at University College London - Ben Cooke, Guy Pollack, Matt Wilde and Tom Wright - have become the talk of the astronomy world.

The rare phenomenon is one of the closest discovered supernovae of its type since 1972, and was found in M82 - known as the cigar galaxy.

A supernova occurs when a star explodes, leaving a glistening fireball in the sky, which fades over a period of around two months.

Hours before the fateful discovery, on January 21, Dr Fossey was in two minds over whether to take the second year students into the dome, as clouds were beginning to close in.

But the students had never looked through a telescope before, and determined not to let them down, he led them to the observatory deck.

The 52-year-old said: “I suppose you could call it instinct. We’ve got a very photogenic galaxy so we took a couple of test shots which came out dull, but I expected that.

“But then I noticed a blob that I had never seen before. I stayed calm and tried not to get my hopes up as sometimes it can just be a camera glitch, or a plane.”

Dr Fossey and the students trawled through archive images of the cigar galaxy and took photos using different filters - and it soon became apparent the mysterious and glittering object was a supernova.

What followed was a series of frantic phone calls to astronomers at Harvard University in Massachusetts as Dr Fossey compiled his report about the wondrous discovery.

He said: “I didn’t get home until 5am. I was excited, I wasn’t tired - I guess I was running on adrenaline. I was in shock and actually felt quite stressed. But by the time I woke up at 9am, I had a message saying it had been confirmed as a supernova.”

Despite the remarkable find, Dr Fossey remains modest. He added: “It’s the first supernova I’ve discovered in my career. It’s very humbling, but it could have happened to anyone. I’m proud to have been the first to spot it.”

Due to the length of time it takes light to reach the Earth, the star, which was once about eight times heavier than the sun, exploded at the time apes still populated the earth and when the Amazon River had not yet formed.

It peaked in brightness in early February, and it can be seen anywhere across the northern hemisphere, including England, America and Japan.

Today, the stunning shot has pride of place on the wall in the observatory.

Natural science student Guy Pollack said: “It was a surreal and exciting experience taking images of the unidentified object as Steve ran around the observatory verifying the result.

“I’m very chuffed to have helped in discovering it.”