The Sun was to be briefly blotted out near here on Wednesday at the start of a total eclipse due to race from tropical northeastern Brazil to the grasslands of Mongolia.

The Moon and Sun were to align from 0836 GMT, casting a 185-kilometer (115-mile) wide lunar shadow on Earth.

The umbra would then track eastwards at dizzying speed across the Atlantic, curve across Africa and the Middle East before expiring in Asia, 14,500 kilometres (9,000 miles) later, according to astronomers' calculations.

Countries whose territory lies directly on this path are Brazil, Ghana, Togo, Benin, Nigeria, Niger, Chad, Libya, Egypt, Greece, Turkey, Georgia, Russia, Kazakhstan and Mongolia, where the eclipse would end at 1148 GMT.

Today's solar eclipse. (Image from NASA TV)

Left: The sun creates a "diamond ring" effect as it emerges after totality. Right: Solar flares, or "prominences" are visible at the edge of the moon's shadow. (Image from NASA TV, caption from NASA.)

The moon's shadow falls over Earth during the eclipse, as seen from the International Space Station 230 miles above. (Image from NASA)