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There’s a great event coming to our neck of the woods soon (by neck-of-the-woods I mean Australasia and South Pacific) – a total solar eclipse, on 14 November (for those like NZ on the west of the international date line) or 13 November (for those on the eastern side – which won’t be many – save the odd ship). The NASA website above gives details in Universal Time (Greenwich Mean Time) and so reports it as 13 November – don’t get confused.

For those lucky enough to be in Cairns, there’s the full spectacle of a total eclipse. For us lesser mortals in NZ, it’s a pretty sizable partial eclipse, especially for those in the north of the North Island. Hamilton gets about 85% coverage at the maximum. (Note that anywhere in NZ will do – even Scott Base in Antarctica, I think, gets a few percent coverage, if you count that as NZ)

For Hamilton, the eclipse starts at about 9:20am, reaches its maximum at 10:30am, then is all done and dusted by 11:45am. Times for the rest of NZ are similar.

I thought hard about travelling over to Cairns for the event. The reason is simple – a large partial eclipse is nothing compared to the experience of a total eclipse. I was fortunate to be able to see the 1999 eclipse in Europe, from a small village in northern Bulgaria,  and, having experienced that, partial eclipses don’t have much interest. But, travel doesn’t come cheaply, and there’s a baby at home, so this time  I’m staying put. While it would be great to see another, I’m happy with one in a lifetime.

So what does a total eclipse give you that a partial one doesn’t. Here’s a list, that’s not at all exhaustive.

1. You get to look at the sun with your naked eye, quite safely.  DON’T do this at any other time.

2. The wispy corona comes into view.

3. If you’re lucky, so does the pink chromosphere (this was particularly prominent in the 1999 eclipse).

4. You get to experience the birds coming down to roost, and then taking off again.

5. If you’re lucky, ‘Baily’s Beads’.

6. Shadow Bands

7. Stars out during the day. Possibly a good view of Mercury, which is hard, though not impossible, to observe well otherwise, because it is so close to the sun.

8. The diamond-ring, as the bright photosphere bursts back into view.

And so forth. One of the things I remember from Bulgaria is just how quickly things went black in the final few seconds before totality. It was like standing in a well lit room and someone turning off a dimmer switch.

So, what do we get for 85% then? Well, not much, actually. You might not even notice that things have gone dim. The human eye is really good at adjusting to different light levels, and it’s really only when only a few percent of the sun remains that you’ll notice any obvious change in illumination. It’s fun to observe the crescent shape of the sun – but do so SAFELY – with decent eclipse glasses or solar projection. A fun thing to do is pinhole projection – put a tiny pinhole in a piece of card and project the sun’s image onto the ground or a sheet of paper.  In Bulgaria we had pinholes provided by way of the old tin roof on the cafe which our group occupied for the event – it was loaded with little tiny holes (not much good in the rain then) which gave some wonderful projections of the sun onto the tables below.

 So, when’s the next total eclipse to hit NZ? There are actually a few coming ‘soon’ – ‘soon’ being used in an astronomical sense. 22 July 2028 sees most of Otago including Dunedin eclipsed totally. But it won’t be an easy eclipse to view, coming near sunset with the sun just 8 degrees above the horizon. The same eclipse, however, tracks right over Sydney (once again the Aussies get it – though there is far more of Australia for an eclipse to hit) so one might be better off heading westward.

But then, like buses, there’s a positive flurry of them. 10 March 2035 sees NZ get an annular eclipse (the moon doesn’t quite cover the whole sun – not as impressive but pretty spooky) – then 13 July 2037 and a total eclipse tracks over the central North Island, including Napier (Hamilton lies just to the north) and then 26 December 2038 we get another chance – this one over Golden Bay, Manawatu (including Palmerston North) and Wairarapa. (Wellington is just off to the south). That will add interest to the Boxing Day barbie on the beach. The really freaky thing is that there is a small slice of land near Waipukurau that will get a total eclipse in both 2037 and 2038.