People standing across a great swathe of the Earth's surface will see the Moon take a big bite out of the Sun.
The solar eclipse was also seen in Turkey this morning.
For North Africa and much of Europe, the event starts at sunrise, whereas in central Russia and north-west China, the spectacle occurs at sunset.
Skywatchers will have to have a high vantage point, however, as both celestial bodies will be skirting the horizon at that time.
As is always the case for solar eclipses, the public is being warned to take great care.
Viewing the Sun's harsh light should only be done through protective equipment - proper solar glasses and solar telescopes, or through a pinhole projection system.
Partial solar eclipses occur when the Sun and Moon do not quite align in the sky as viewed from Earth, and the deep shadow cast by the smaller body passing across the bigger one just misses the planet.
Four partial solar and two total lunar eclipses will take place in 2011.
