Partial Solar Eclipse visible from North America

Next Thursday, a partial solar eclipse will be visible across North America in the late afternoon. From Canada, the Moon will obscure up to 75% of the Sun’s light, and from the US up to 65% of the Sun’s disk will be covered.

Solar eclipses occur when the Sun, Moon and Earth are aligned in an almost exactly
straight line, with the Moon in the middle, such that the Moon passes in
front of the Sun.

On this occasion, the alignment will not be very exact, and while the
Moon will brush the side of the Sun – a partial solar eclipse –
nowhere on Earth will see it entirely cover the Sun’s disk.

The eclipse will only be visible from North America
because the Moon is so close to the Earth – 390 times closer than the Sun
– that its position in the sky differs by up to two degrees (four times
its diameter) from one side of the Earth to the other. So, while it may cover
the Sun as seen from the US, it may not even touch it as seen from the
southern hemisphere.

The globe above shows the path of the Moon’s shadow across the Earth during the
eclipse. The shaded region within the red contour shows all of the places where
the Moon covers any part of the Sun’s disk. Within this, white contours show
where the Moon covers 20%, 40%, 60% and 80% of the Sun. The central white dot
shows places where the Moon covers more than 98% of the Sun.

The geometry of a lunar eclipse

Solar eclipses take place when the Earth moves through the Moon’s umbra or penumbra. Partial eclipses are seen from any parts of the Earth’s surface which pass through the Moon’s penumbra; a total eclipse is only seen when the Earth’s surface passes within the Moon’s umbra. Image courtesy of F. Sogumo.

The map below shows a projection of the Moon’s shadow onto a map of the world,
with the same contours marked.

The eclipse will be best seen from the following countries: Canada (Sun 75% covered), United States (Sun 65% covered), Russia (Sun 50% covered) and Mexico (Sun 30% covered).

From the UK, the eclipse will not be visible as the Sun will be below the horizon at the time. For detailed information about other locations, see

The map below shows contours of the maximum extent of the eclipse across the world.

Map of the total solar eclipse of October 2014

The charts and text above were taken from

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