Solar eclipse 2015: When is it, what time will it start and where can I go to see it?

Nothing prepares you for a total solar eclipse. We have seen six, and - believe us – it is both a magnificent and a terrifying experience

On 20 March, at 9.41 in the morning, the Faroe Islands will be plunged into darkness (AFP)

On 20 March, at 9.41 in the morning, the Faroe Islands will be plunged into darkness. No – the islanders won’t be suffering a power-cut, but experiencing a total eclipse of the Sun. The last one visible from these shores was on 11 August 1999, and the next to be seen from mainland Britain won’t be until 23 September 2090.

Strictly speaking, the Faroes aren’t British, but Danish. However, they are easy to reach from the UK - and thousands of eclipse-chasers will be invading the islands for the spectacle.

On paper, eclipses of the Sun sound rather prosaic. They take place when the Moon passes in front of the Sun. The coincidence is that the Sun is 400 times wider that the Moon; but it lies 400 times further away. If you’re in exactly the right spot on Earth, the overlap is exact.

As the eclipse progresses, you’ll notice a marked drop in temperature. The air becomes damper, and the sky grows darker. Minutes before totality, the light takes on a weird flat, filmic appearance.

Then – when you least expect it – totality! And time to whip off the goggles: the totally-eclipsed Sun is safe to look at. If you’re an ‘eclipse virgin’, you will be frightened by the sight before your eyes. Where has our friendly Sun gone? It has been transformed into a Chinese dragon-mask, the tendrils of its pearly atmosphere wrapped around the black body of the Moon. Look carefully at the edge of the Moon, and you’ll spot crimson prominences: great magnetic arches in the Sun’s lower atmosphere.

If you can tear yourself away from gawping at the Sun, you may catch the planets Venus, Mars and Mercury shining in the dark sky.

All too quickly, it’s over: in this case, in 2 minutes 2 seconds. You’ll see a chink of the Sun emerging from behind a gap in the Moon’s rugged limb: the glorious ‘diamond ring’ effect. Goggles on!

Things so rapidly return to ‘normal’ that you think you’ve dreamt it. But you haven’t: everyone is whooping and hugging each other, and asking ‘where to next time?’

If you can’t get to the Faroes, don’t feel that you’ve completely missed out. All over Britain, the eclipse is a massive partial: 94% from Aberdeen; 87% from London; and 88% from Penzance. You will see darkening skies, and feel the chill coming on.

But you won’t see the Sun’s delicate outer atmosphere during this partial eclipse: there’s still too much sunlight around. AND YOU MUST WEAR ECLIPSE GOGGLES THROUGHOUT.

When to look?

These timings are based on London; they change by a few minutes up and down the country.

Start: 8.25am

Mid-eclipse: 9.31am

Eclipse ends: 10.41am

Fingers crossed for clear skies!

What's up

The gentle spring stars are making a welcome return to our skies, chasing away the steely-blue orbs of winter. Look out for the graceful sickle of Leo the Lion’s head; followed by Y-shaped Virgo in the East.

The brilliant planet Jupiter still sails high in the south, next to Leo’s sickle. But it is being challenged by dazzling Venus, setting in the west. By the end of the month – after the clock-change – the Evening Star sets at 11pm, and outshines everything in the sky except the Sun and Moon.

Diary

March 2: 6.05pm - Full Moon

March 13: 5.48pm - Moon at Last Quarter

March 20: 8.25am - 10.41am - Eclipse of the Sun (total in the Faroes and Svalbard); 9.26am New Moon; 10.45pm Vernal Equinox (start of Spring)

March 27: 7.42am - Moon at First Quarter

March 29: 1.00am - BST begins – clocks forward one hour (‘Spring forward, Fall back’)