The Nördlinger Ries is an

impact crater An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal c ...

and large circular depression in western

Bavaria Bavaria, officially the Free State of Bavaria, is a States of Germany, state in the southeast of Germany. With an area of , it is the list of German states by area, largest German state by land area, comprising approximately 1/5 of the total l ...

and eastern

Baden-Württemberg Baden-Württemberg ( ; ), commonly shortened to BW or BaWü, is a states of Germany, German state () in Southwest Germany, east of the Rhine, which forms the southern part of Germany's western border with France. With more than 11.07 million i ...

. It is located north of the

Danube The Danube ( ; see also #Names and etymology, other names) is the List of rivers of Europe#Longest rivers, second-longest river in Europe, after the Volga in Russia. It flows through Central and Southeastern Europe, from the Black Forest sou ...

in the district of Donau-Ries. The city of Nördlingen is located within the depression, about south-west of its centre.

Etymology

"Ries" is derived from

Raetia Raetia or Rhaetia ( , ) was a province of the Roman Empire named after the Rhaetian people. It bordered on the west with the country of the Helvetii, on the east with Noricum, on the north with Vindelicia, on the south-west with Transalpine ...

, since the tribe of Raetians lived in the area in pre- Roman times.

Description

The depression is a

meteorite A meteorite is a rock (geology), rock that originated in outer space and has fallen to the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical ...

formed 14.808 ± 0.038 million years ago in the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

. The crater is most commonly referred to simply as the ''Ries crater'' or ''the Ries''. The original crater rim had an estimated diameter of . The present floor of the depression is about below the eroded remains of the rim. It was originally assumed that the Ries was of

volcanic A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

glacial A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

tectonic Tectonics ( via Latin ) are the processes that result in the structure and properties of the Earth's crust and its evolution through time. The field of ''planetary tectonics'' extends the concept to other planets and moons. These processes ...

origin. Oliver Sachs introduced, in this context, the term "pioneer era" (up to 1870) and marked the beginning of early modern research on the Ries (from 1870), meaning the period when the first detailed theories about the formation of the Nördlinger Ries became known. In 1960 Eugene Shoemaker and

Edward C. T. Chao Edward Ching-Te Chao (; November 30, 1919 – February 3, 2008) was one of the founders of the field of impact metamorphism, the study of the effects of meteorite impacts on the Earth's crust. Born in Suzhou, China, he was best known for di ...

showed that the depression was caused by meteorite impact. The key evidence was the presence of

coesite Coesite () is a form (polymorphism (materials science), polymorph) of silicon dioxide (silicon, Sioxide, O2) that is formed when very high pressure (2–3 gigapascals), and moderately high temperature (), are applied to quartz. Coesite was first ...

, which, in unmetamorphosed rocks, can only be formed by the shock pressures associated with meteorite impact. The coesite was found in suevite from Otting quarry, but even before, Shoemaker was encouraged by St. George's Church in Nördlingen, which is built of locally derived suevite. The suevite was formed from mesozoic sediments shocked by the

bolide A bolide is normally taken to mean an exceptionally bright meteor, but the term is subject to more than one definition, according to context. It may refer to any large Impact crater, crater-forming body, or to one that explodes in the atmosphere. ...

impact. The Ries impact crater was a rampart crater, thus far a unique finding on Earth. Rampart craters have almost exclusively been found on

Mars Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...

. Rampart craters exhibit a fluidized ejecta flow after the impact of the meteorite, most simply compared to a bullet fired into the mud, with the ejecta resembling a mudflow. Another impact crater, the much smaller ( diameter) Steinheim crater, is located about west-southwest from the center of Ries. It had previously been thought that the two craters formed simultaneously by the impact of a

binary asteroid A binary asteroid is a system of two asteroids orbiting their common barycenter. The binary nature of 243 Ida was discovered when the Galileo spacecraft flew by the asteroid in 1993. Since then numerous binary asteroids and several triple a ...

14.8 million years ago, but a study published in 2020 suggests that Steinheim could actually be about 500,000 years younger than Nördlinger Ries. Recent computer modeling of the impact event indicates that the impactors probably had diameters of about (Ries) and (Steinheim), had a pre-impact separation of some tens of kilometers, and impacted the target area at an angle around 30 to 50 degrees from the surface in a west-southwest to east-northeast direction. The impact velocity is thought to have been about . The resulting explosion had the power of 40 million Hiroshima bombs, an energy of roughly 2.4

joule The joule ( , or ; symbol: J) is the unit of energy in the International System of Units (SI). In terms of SI base units, one joule corresponds to one kilogram- metre squared per second squared One joule is equal to the amount of work d ...

s. The Ries crater impact event is believed to be the source of moldavite tektites found in southern

Bohemia Bohemia ( ; ; ) is the westernmost and largest historical region of the Czech Republic. In a narrow, geographic sense, it roughly encompasses the territories of present-day Czechia that fall within the Elbe River's drainage basin, but historic ...

and

Moravia Moravia ( ; ) is a historical region in the eastern Czech Republic, roughly encompassing its territory within the Danube River's drainage basin. It is one of three historical Czech lands, with Bohemia and Czech Silesia. The medieval and early ...

(

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

). The tektite melt originated from a sand-rich surface layer that was ejected to distances up to downrange of the crater. The shape of the strewnfield suggests that the direction of impact was from the west-southwest. Stone buildings in Nördlingen contain millions of tiny

diamond Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of e ...

s, all less than across. The impact that caused the Nördlinger Ries crater created an estimated of them when it impacted a local

graphite Graphite () is a Crystallinity, crystalline allotrope (form) of the element carbon. It consists of many stacked Layered materials, layers of graphene, typically in excess of hundreds of layers. Graphite occurs naturally and is the most stable ...

deposit. Stone from this area was quarried and used to build the local buildings.

History

On one edge of the Nördlinger Ries are the Ofnet Caves, where, at the beginning of the 20th century, archaeologists discovered thirty-three human skulls dating to the

Mesolithic The Mesolithic (Ancient Greek language, Greek: μέσος, ''mesos'' 'middle' + λίθος, ''lithos'' 'stone') or Middle Stone Age is the Old World archaeological period between the Upper Paleolithic and the Neolithic. The term Epipaleolithic i ...

period. The Ries was the site of the Battle of the Ries on 13 May 841. The landing site for

Apollo 14 Apollo 14 (January 31February 9, 1971) was the eighth crewed mission in the United States Apollo program, the third to Moon landing, land on the Moon, and the first to land in the Geology of the Moon#Highlands, lunar highlands. It was the las ...

is a heavily craterized terrain, and one of the science goals of the mission was to sample ejecta from the impact that formed

Mare Imbrium Mare Imbrium (Latin ''imbrium'', the "Sea of Showers" or "Sea of Rains") is a vast lunar mare, lava plain within the Imbrium Basin on the Moon and is one of the larger craters in the Solar System. The Imbrium Basin formed from the collision ...

. Nördlinger Ries is an easily accessible, large impact crater, making it a convenient analog for lunar craters. Because of this, it was used as a location to train Apollo 14 astronauts, so that they would be able to investigate lunar impact structures and related rocks. Astronauts

Alan Shepard Alan Bartlett Shepard Jr. (November 18, 1923 – July 21, 1998) was an American astronaut. In 1961, he became the second person and the first American to travel into space and, in 1971, he became the List of Apollo astronauts#Apollo astr ...

and

Edgar Mitchell Edgar Dean "Ed" Mitchell (September 17, 1930 – February 4, 2016) was a United States Navy officer and United States Naval Aviator, aviator, test pilot, Aerospace engineering, aeronautical engineer, Ufology, ufologist, and NASA astronaut. ...

, as well as Apollo 14 backup astronauts

Eugene Cernan Eugene Andrew Cernan (; March 14, 1934 – January 16, 2017) was an American astronaut, United States naval aviator, naval aviator, electrical engineer, aeronautical engineer, and fighter pilot. Cernan traveled into space three times and ...

and

Joe Engle Joe Henry Engle (August 26, 1932 – July 10, 2024) was an American pilot, aeronautical engineer, and NASA astronaut. He was the commander of two Space Shuttle missions including STS-2 in 1981, the program's second orbital flight. He also flew ...

, trained here from August 10 to August 14, 1970.

References

External links

Ries at Earth Impact Database

{{DEFAULTSORT:Nordlinger Ries Impact craters of Germany Miocene impact craters Miocene Germany Paleontological sites of Europe Landforms of Bavaria Landforms of Baden-Württemberg Natural regions of the Swabian Keuper-Lias Plains Geological type localities Donau-Ries