For several hours, as Earth stops more and more of the sun’s light falling upon the lunar surface, the normally bright full moon darkens and turns red before slowly recovering its usual lustre. I’m a huge fan of lunar eclipses and will be heading out on Friday to make the most of this celestial treat.
Technically, this week’s event isn’t a total eclipse of the moon. In fact, the moon is skirting the edge of Earth’s dark umbral shadow. Greatest eclipse occurs at 10.04pm when 97% of the lunar surface will be in shadow. At that time, if you look carefully, you should see that there’s a really bright spot at the top-right edge where bright sunlight is still illuminating the moon.
Incidentally, at mid-eclipse, the moon will be quite low in the sky, standing just 12 degrees above the northeast horizon, quite close to Matariki. This should make for really super photographic opportunities.
To truly enjoy this week’s eclipse I think it is important, if you can, to observe from a location well away from bright lights. I was lucky to observe this year’s first lunar eclipse, back in May, from the University of Canterbury’s observatory atop Mt John. I was completely overwhelmed at how dark it got in the middle of the eclipse. I think eclipses lose some of their majesty and impact when observed from a town or a city.
In Dunedin, the moonrise occurs at 8.45pm. This itself will be an amazing sight, since the bottom third of the moon will already be covered by Earth’s shadow. With the maximum eclipse at 10.04, the main part of the eclipse will be over by 11.47pm, when the dark part of Earth’s shadow departs.
