Tonight, the moon will be at its closest point to the Earth in 68 years.

It might seem like the stuff of science fiction, but did this so-called 'supermoon' have anything to do with the powerful earthquakes that rocked New Zealand this morning?

Seismologist for GNS Science Dr John Ristau says it's entirely plausible the supermoon could be a factor.

"When you get the tidal forces from the moon it does cause increased stresses in the Earth's crust, so what can happen, potentially, is if you did have a fault that was almost at the very tipping point of rupturing, this could potentially act as the straw that broke the camel's back."

Looking at previous supermoons and possible connections to other major earthquakes, there was a supermoon on March 19 2011, eight days after the massive earthquake and tsunami that hit Japan.

On February 22 that year, Christchurch of course suffered a devastating quake in which 185 people died.

Like the previously unknown fault that ruptured under Christchurch in 2011, Dr Ristau says the one in north Canterbury is also unknown, and could have been near its tipping point.

"If you had a fault that was right there and was just about to break, all it needs is just one tiny little push. So that tiny little push, it could coincidentally happen at the time when there's a full moon, when the tidal forces are high."

Strangle lights were also seen the skies last night. The lights appeared exactly when the quake occurred and were filmed in Wellington: