'... no problem – five kilowatts of lighting strung up on the ship. Like a Christmas tree – beautiful, shining right through the ice. Glorious colours. Lee saw it first – a huge dark mass rising up from the depths. At first we thought it was a school of fish – too large for a single organism – then it started to break through the ice.

'... like huge strands of wet seaweed, crawling along the ground. Lee ran back to the ship to get a camera – I stayed to watch, reporting over the radio. The thing moved so slowly I could easily outrun it. I was much more excited than alarmed. Thought I knew what kind of creature it was – I've seen pictures of the kelp forests off California – but I was quite wrong...

I could tell it was in trouble. It couldn't possibly survive at a temperature a hundred and fifty below its normal environment. It was freezing solid as it moved forward – bits were breaking off like glass – but it was still advancing towards the ship – a black tidal wave, slowing down all the time.

'I was still so surprised that I couldn't think straight and I couldn't imagine what it was trying to do.

'... climbing up the ship, building a kind of ice tunnel as it advanced. Perhaps this was insulating it from the cold – the way termites protect themselves from Sunlight with their little corridors of mud.

'... tons of ice on the ship. The radio antennas broke off first. Then I could see the landing legs beginning to buckle – all in slow motion, like a dream.

'Not until the ship started to topple did I realize what the thing was trying to do – and then it was too late. We could have saved ourselves – if we'd only switched off those lights.

'Perhaps it's a phototrope, its biological cycle triggered by the Sunlight that filters through the ice. Or it could have been attracted like a moth to a candle. Our floodlights must have been more brilliant than anything that Europa has ever known.