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Estimated at over 60 tons, the Hoba meteorite (also known as Hoba West meteorite) is the largest known meteorite and the most massive naturally-occurring piece of iron known at the Earth's surface. It was named after its discovery locality, the Hoba West Farm near Grootfontein, Namibia. It has been excavated, but because of its size and mass has never been moved from the discovery site.

The Hoba meteorite is estimated to have landed over 80,000 years ago. It is inferred that the Earth's atmosphere slowed the object down to the point that it fell to the surface at terminal velocity, thereby remaining intact, and causing little excavation. The meteorite is unusual in that it is flat on both major surfaces, possibly causing it to have skipped across the top of the atmosphere in the way a flat stone skips on water.

Description and composition

The Hoba meteorite is a tabloid body of metal, measuring 2.7 by 2.7 metres (8 feet 9 inches) by 0.9 meters (3 feet). In 1920 its mass was estimated at 66 tons. Erosion, scientific sampling and vandalism have reduced its mass over the years. The remaining mass is currently estimated at just over 60 tons. The meteorite is composed of about 84% iron and 16% nickel, with traces of cobalt. It is classified as a nickel-rich ataxite. A crust of iron hydroxides is locally present on the surface due to weathering.

Discovery

The Hoba meteorite left no preserved crater, and its discovery was a chance event. The owner of the land is said to have encountered the object while ploughing one of his fields with an ox. During this task, the farmer heard a loud metallic scratching sound, before his plough came to a sudden stop. The meteorite was excavated soon after, and identified and described by scientist J. Brits, who's report was published in 1920; this report can be viewed at the Grootfontein Museum in Namibia.

Modern History

In the attempt to control vandalism, the Government of Namibia, then South West Africa, declared the Hoba meteorite to be a National Monument in March 1955. In 1985, Rossing Uranium Ltd. made resources and funds available to the Namibian Government to provide additional protection against vandalism. The owner of the Hoba West farm donated the meteorite and the site where it lies to the State for "educational" purposes in 1987. Later that year, the Government opened a tourist centre at the site. As a result of these developments, vandalism of the Hoba meteorite has ceased, and it is now visited by thousands of tourists every year.

Sources

Universe: The Definitive Visual Dictionary, Robert Dinwiddie, DK Adult Publishing, (2005), pg. 223.

19°35′33″S 17°56′01″E / 19.59250°S 17.93361°E / -19.59250; 17.93361

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 [[Image:Hoba_Meteorite.jpg|thumb|right|The Hoba meteorite.]]
 [[Image:Hoba meteorite00.jpg|thumb|right|The Hoba meteorite in [[1967]].]]
-The '''Hoba meteorite''', also known as the '''Hoba West meteorite''', is the heaviest [[meteorite]] in the world and the largest naturally-occurring mass of [[iron]] known to exist on the surface of the earth. The meteorite, named after the Hoba West Farm near [[Grootfontein]], [[Namibia]], where it was discovered in [[1920]], has not been moved since it landed over 80,000 years ago. The discovery of the Hoba meteorite was a chance find, as it left no [[Impact crater|crater]] or other sign of impact; evidently the [[Earth's atmosphere]] slowed down the 66-ton iron body enough so that it fell at [[terminal velocity]]. At this speed, the meteorite stayed basically intact, and the low-energy impact with the surface caused little excavation. The meteorite is unusual in that it is flat on both major surfaces, possibly causing it to have skipped across the top of the atmosphere in the way a flat stone [[stone skipping|skips]] on water.
+Estimated at over 60 tons, the '''Hoba meteorite''' (also known as '''Hoba West meteorite''') is the largest known [[meteorite]] and the most massive naturally-occurring piece of [[iron]] known at the Earth's surface. It was named after its discovery locality, the Hoba West Farm near [[Grootfontein]], [[Namibia]]. It has been excavated, but because of its size and mass has never been moved from the discovery site.
+The Hoba meteorite is estimated to have landed over 80,000 years ago. It is inferred that the [[Earth's atmosphere]] slowed the object down to the point that it fell to the surface at [[terminal velocity]], thereby remaining intact, and causing little excavation. The meteorite is unusual in that it is flat on both major surfaces, possibly causing it to have skipped across the top of the atmosphere in the way a flat stone [[stone skipping|skips]] on water.
-The Hoba meteorite is a tabloid body of metal, measuring 2.7 by 2.7 metres (8 feet 9 inches) by 0.9 meters (3 feet). Its mass in 1920 was estimated at 66 tons. Erosion, scientific sampling and vandalism took their toll and over the years the meteorite shrank to just over 60 tons. This led the Government of Namibia then ([[South West Africa]]) to declare the Hoba meteorite a National Monument in March [[1955]], in order to forestall further vandalism.
+==Description and composition==
-The meteorite is composed of 84% iron and around 16% [[nickel]] with some traces of [[cobalt]]. There are crusts of iron [[hydroxide]]s on the surface in parts. In scientific terms, the meteorite is classed as a nickel-rich [[ataxite]].
+The Hoba meteorite is a tabloid body of metal, measuring 2.7 by 2.7 metres (8 feet 9 inches) by 0.9 meters (3 feet). In 1920 its mass was estimated at 66 tons. Erosion, scientific sampling and vandalism have reduced its mass over the years. The remaining mass is currently estimated at just over 60 tons. The meteorite is composed of about 84% iron and 16% [[nickel]], with traces of [[cobalt]]. It is classified as a nickel-rich [[ataxite]]. A crust of iron [[hydroxide]]s is locally present on the surface due to weathering.
+==Discovery==
-The Hoba meteorite was discovered by the owner of the Hoba West farm and was identified and described soon after by the scientist J. Brits. His original report (1920) can be seen at the [[Grootfontein Museum]] in Namibia. The owner of the land is said to have encountered the giant meteorite while ploughing one of his fields with an [[cattle|ox]]. During this task, the farmer heard a loud, metallic, scratching sound before his plough came to a dead stop. The farmer uncovered the meteorite soon after.
+The Hoba meteorite left no preserved [[Impact crater|crater]], and its discovery was a chance event. The owner of the land is said to have encountered the object while ploughing one of his fields with an [[cattle|ox]]. During this task, the farmer heard a loud metallic scratching sound, before his plough came to a sudden stop. The meteorite was excavated soon after, and identified and described by scientist J. Brits, who's report was published in 1920; this report can be viewed at the [[Grootfontein Museum]] in Namibia.
+==Modern History==
-In [[1985]], [[Rossing]] Uranium Ltd. made resources and funds available to the Namibian Government so that additional protection against vandalism could be provided. The owner of the farm Hoba West donated the meteorite and the site where it lies to the State for "educational" purposes in 1987. Later that year, the Government opened a tourist centre at the site. As a result of these developments, vandalism of the Hoba meteorite has ceased. It is visited by thousands of tourists every year.
+In the attempt to control vandalism, the Government of Namibia, then [[South West Africa]], declared the Hoba meteorite to be a National Monument in March [[1955]]. In [[1985]], [[Rossing]] Uranium Ltd. made resources and funds available to the Namibian Government to provide additional protection against vandalism. The owner of the Hoba West farm donated the meteorite and the site where it lies to the State for "educational" purposes in 1987. Later that year, the Government opened a tourist centre at the site. As a result of these developments, vandalism of the Hoba meteorite has ceased, and it is now visited by thousands of tourists every year.
 ==Sources==