Supermoon 2014: what it is and how to see it

A supermoon rises behind a Greek temple

Everything you need to know ahead about the last supermoon of 2014, which falls tomorrow

LAST UPDATED AT 14:34 ON Mon 8 Sep 2014

The moon will appear particularly large and bright tomorrow night, in the last of three 'supermoon' events this summer. Clear skies are predicted across much of the country, providing good viewing conditions for the natural phenomenon. 

What is a supermoon?

Supermoon events cause the moon to appear at its largest and brightest. They occur when the full moon coincides with the satellite reaching the closest point to Earth in its elliptical orbit – known as the perigee. When in perigee, the moon is just 360,000km away from us, and around 50,000km closer than when it is at its apogee, the furthest it gets from earth.

Where did the name come from?

Astrologer Richard Nolle coined the term, back in 1979. As Nasa scientist James Garvin explains in International Business Times: "It is called a supermoon because this is a very noticeable alignment that, at first glance, would seem to have an effect. The 'super' in supermoon is really just the appearance of being closer."

How often do they happen?

Unlike other celestial events, supermoons are actually relatively common. They generally happen around once a year, though there have been three in swift succession this summer. 

When is the next supermoon?

The third supermoon of the summer will take place on 9 September, when the moon will be 358,387km away, according to The Independent. That's not quite as close as it was on 10 August, when it was 356,896km away at its closest point. We won't see another supermoon for just over a year: the next one falls on 28 September 2015. 

What is the best way to view supermoons?

Lunar buffs at recommend viewing the supermoon just after it rises or before it sets, when it is close to the horizon. If you watch as it dips behind buildings or trees, an optical illusion is produced, which makes the moon seem even larger than it really is.

Will these supermoons have any impact on earth?

Full moons generally cause spring tides, and the next three supermoons will cause perigean spring tides, where tides will be at most a matter of inches higher than normal. Scientists say it is unlikely that the coming tides will cause any flooding, unless they coincide with a particularly strong weather system.

Speculation that a previous supermoon caused the Japanese earthquake has been dismissed by Nasa. However, British coastguards have blamed a previous supermoon for the stranding of several ships.

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