The Super Blue Blood Moon of 2018

Being old and fragile, I seldom stay awake for forty-eight consecutive hours these days (though when I was younger I used to do it quite frequently – sleep is for wimps; it wastes far too  much time that would be better spent doing fun things). But sometimes life doesn't give you any choice. At the beginning of this year New Zealand was blessed with a blue moon, a supermoon and a lunar eclipse (a blood moon) all taking place simultaneously over one evening from about 11.00pm until about 3.00am the next day. The last time that combination of events happened was in 1866 and I missed seeing it then because I was born 84 years too late – a considerable margin of error indicative of very bad planning on my part. I determined not to make the same mistake this time around.

Despite the famous proverb, a blue moon is actually quite a common thing. It is the name given to the second of two full moons which occur in the same calendar month, and it happens every couple of years or so.  

A supermoon is a full moon that coincides with the moon's closest approach to the Earth. Technically it's known as a perigee syzygy, but that's far too much of a mouthful for comfort so most people use the more colloquial term supermoon instead. Visually, a supermoon appears to be about 14% larger, and about 30% brighter, than normal. The effect is most marked when the moon is near the horizon, and it can appear to be quite gigantic.

A lunar eclipse, of course, takes place when the moon passes through the shadow that the Earth casts when the sun is behind it. And the lunar eclipse of January 2018, coinciding with a blue moon and a supermoon, would be a blood moon because the sunlight reflected from the moon's surface would be refracted through the Earth's atmosphere, and the angle of refraction would gave the moon a red tinge. It's caused by the same effect that often makes sunrise and sunset appear quite red. In the jargon, the phenomenon is known as Rayleigh scattering and there was a time when I could have described it mathematically – but it has been far too many years since I last did any serious physics and maths and sadly that knowledge has now vanished from my mind.

Anyway, excitingly, for the first time since 1866 we were due to have a super blue blood moon. Naturally Robin and I had to stay up all night to watch it. Perhaps Jake the Dog would want to see it as well.

We had about a week of completely cloudless skies before the great event occurred, so everyone was optimistically certain that the trend would continue, and that the night of the eclipse would provide excellent viewing. But nature is perverse, and that evening New Zealand was almost completely covered with thick clouds. Most astronomically inclined New Zealanders took to their beds severely annoyed with the weather gods. But the small area of New Zealand where I live was reasonably cloudless because Jake and I had both had the foresight to sacrifice a bone and pee on a sundial. Consequently the weather gods were pleased with us and so the visibility was good.

This wasn't my first lunar eclipse. I've seen several others. Probably the most memorable one was some time in the mid 1980s when I was on holiday in America. That eclipse happened while I was in New Orleans and I watched it take place from the deck of a riverboat cruising on the Mississippi. I found the experience to be incredibly spine-tingling and romantic, but of course the eclipse that I saw then didn't coincide with a supemoon. I was eagerly anticipating that New Zealand's super blue blood moon would be considerably more dramatic than any I'd ever seen before.

I told our next door neighbour that Robin and I were planning on watching it. "Oh," she said when I explained its significance, "ring my doorbell and wake me up when the drama happens. I'd like to see that."

From the moment the moon rose into the sky it was dazzlingly bright. I prepared copious coffee and set up an intravenous drip. I kept popping outside to check on the moon's progress. About 11.00pm, as promised, the shadow of the Earth started to eat up the disc of the moon. Over several hours the area of the moon eclipsed by the shadow gradually got larger and the red colour became more and more prominent. It was particularly dramatic when seen through binoculars. Our next door neighbour came out to join us and she was quite overwhelmed by the beauty of it. "Isn't nature wonderful," she said.

I could only agree with her. "When nature wants to, she is very good at putting on a dramatic spectacle," I said.

Disappointingly, Jake had put himself to bed hours before and he refused to come out and look at the eclipsing moon. He really couldn't see what all the fuss was about. "So it's a super blue blood moon," he said. "So what? I can't chase it, eat it, bury it or play tug of war with it. I suppose I could howl at it, but if I did you'd only tell me off for waking everybody up. So what possible use is it?'

"You're a philistine," I told him.

"That's right," he said. "Wake me when it's time for my next walk." He tucked his nose underneath his tail and went back to sleep.

In the whole of our street, only Robin and I and our next door neighbour were watching the drama taking place overhead. "Doesn't anybody else care about it?" I asked. "Are they all really that incurious?"

"I suspect it's more that they have to go to work in the morning," said Robin. "They need their sleep. We're the only retired people around here. It doesn't matter if we nod off in the middle of a conversation tomorrow."

"You're probably right," I said.

Every so often a small wisp of cloud drifted in front of the increasingly ruddy moon and obscured the view. But the effect never lasted more than a few minutes, and it was never very long before the moon was back, redder than before. By about 3.00am the eclipse was total and the disc of the moon hung bloodily in the sky. It looked for all the world as if the planet Mars had left its orbit and come for a baleful visit.

Robin and our neighbour both went back to bed now that they had seen everything that there was to be seen. But I stayed up because I wanted to watch the effect unwind itself. I topped up my coffee drip and kept an eye on what was going on overhead.

Slowly the moon crept back out from beneath the shadow of the Earth and the red glow faded away from it. As dawn arrived everything was back to normal and there was absolutely no sign at all that anything extraordinary had taken place while the world slept. By now, I had my second wind and I felt quite bouncy. I took Jake for his morning walk and we started our brand new day together.

The next night the sky over New Zealand was completely cloudless again. Clearly the clouds that had obscured our view on the night of the eclipse were the result of a government conspiracy. No other explanation was possible. I discussed it with Jake, making sure that we were both wearing colanders on our heads so that we couldn't be spied on and monitored.

"Write a letter to The Times," Jake suggested. "And sign it Disgusted, Tunbridge Wells."