Meteor Crater, Arizona: diameter 1,265 metres (4,150 feet)

Wolf Creek, Australia: 850 m (2,789 ft)

Henbury, Australia: 220 m (722 ft)

Boxhole, Australia: 175 m (574 ft)

Odessa, Texas: 170 m (558 ft)

Tswainga, South Africa: 132 m (433 ft)

Wabar, Saudi Arabia: 116 m (381 ft)

Oesel, Estonia: 100 m (328 ft)

Campo del Cielo, Argentina: 75 m (246 ft)

Dalgaranga, Australia: 70 m (230 ft)

Meteor Crater, Arizona

Meteor Crater (also known as the Barringer Crater) is 30.6 kilometres (19 miles) west of Winslow, Arizona. The first accounts of it appeared in 1871, but it is estimated to have been created 50,000 years ago by a nickel-iron lump weighing 300,000 tonnes and travelling at 65,000 kmph (40,390 mph). Measuring 1,265 m (4,150 ft) across by 175 m (574 ft) deep, it is the world's best-preserved crater and is now a big tourist attraction (www.barringercrater.com).

At the end of the 1880s, pieces of iron were found there and identified as meteorites, but early geologists believed the crater itself was of volcanic origin. Then, in 1905, Daniel Barringer, a mining engineer with an eye for business, attempted to dig out the huge iron he believed had made the hole. However, by the 1920s, scientists realised that it had vaporised on impact. Altogether, 30 tonnes of meteorites have been found in the vicinity, the largest weighing 635 kg (1,400 lb).

Chicxulub

On the Yucatán coast of Mexico, buried beneath the village of Puerto Chicxulub, is the impact crater responsible for the catastrophic climatic conditions — fires, darkness, acid rain — that killed off the dinosaurs 65 million years ago.

The site was first discovered in 1978 by a geophysicist contracted by the Mexican oil company Pemex to survey the area for drilling. When a global layer of sediment containing traces of the metal iridium (dust that comes mainly from space) separating the Cretaceous and Tertiary periods was discovered, the search for a crater was on.

Describing the meteoritic impact itself in Fire on Earth, John and Mary Gribbin have written: 'It was the equivalent of a rock the size of Mount Everest, travelling ten times faster than the fastest bullet, producing an impact so severe that the entire Earth shifted in its orbit by a few dozen metres and the length of the year changed by a few hundredths of a second.'

Henbury

In 1931, 13 craters were discovered south of Alice Springs in Australia, in an oval-shaped area of just over 1 sq. km (0.39 sq. mile). The biggest one measures 220 m (722 ft) by 110 m (361 ft), and the layout suggeststhat the meteoroid must have disintegrated just before hitting land. To the Aborigines, the site is known as 'sun trail fire devil rock', which indicates that their ancestors may have witnessed the fall. Analysis of particles of fused glass found in the craters points to an age of less than 10,000 years.

Wabar

These three craters, filled by sand, are to be found in the middle of the Saudi desert's 'empty quarter', 550 km (342 miles) from Riyadh. The largest is 116 m (381 ft) across and is estimated by US Geological Survey scientist Jeff Wynn to be the crash site of an iron with a mass of around 3,000 tonnes, which landed no more than 450 years ago. Black melted slag at the site shows that intense heat turned the sand into glass. The site was first discovered in 1931, but it wasn't until 1965 that iron remains were found embedded in the sand, the largest chunk weighing 10 tonnes.