What is the largest meteorite

Largest German stone meteorite found in Blaubeuren

The 30 kilogram 'Blaubeuren' meteorite
Image 1/8, Credit: Gabriele Heinlein

The 30 kilogram 'Blaubeuren' meteorite

A scientific sensation: in 1989, while digging a cable trench on his property in Blaubeuren near Ulm, a house owner came across a stone that seemed unusually heavy and had magnetic properties. After that, the angular chunk lay in the garden for decades. It wasn't until 31 years later that the finder wanted to be certain whether it might be a meteorite and reports his find to the German Aerospace Center (DLR) in January 2020. Just a few days later it was clear: The find was a stone meteorite - with a mass of more than 30 kilograms, the largest ever found in Germany. Presumably, 'Blaubeuren', the official name given to the find by the Meteoritical Society, fell on earth several hundred years ago because its exterior shows strong signs of weathering.
The first clear indication that 'Blaubeuren' is a meteorite
Image 2/8, Credit: Gabriele Heinlein

The first clear indication that 'Blaubeuren' is a meteorite

After submitting the photos, the finder sent a 23.4 gram fragment, chopped off from the main mass of the 'Blaubeuren', to the DLR meteorite expert Dieter Heinlein. After a visual inspection, the expert first guessed iron ore, but then he picked up the diamond saw and cut open the small piece: In doing so, Dieter Heinlein saw a matrix of millimeter-small chondrules, spheres that were typical for stone meteorites, that were formed when the solar system formed. Created 5 billion years ago and represent the basic building blocks of all planets. He also discovered typical inclusions of metals. This ensured that this fragment was already a piece of a meteorite.
Blaubeuren thin sections under the polarizing microscope
Image 3/8, Credit: Addi Bischoff, Institute for Planetology, WWU Münster.

Blaubeuren thin sections under the polarizing microscope

The 'Blaubeuren' meteorite falls into the class of a so-called H4-5 chondritic breccia in the system of stone meteorites. When examining wafer-thin, light-transmitting rock sections, usually 25 micrometers (thousandths of a millimeter) thick, and using polarized light, the rock-forming minerals can be determined in characteristic colors and outlines. 'Blaubeuren' contains numerous crystallized melt droplets with round outlines, the so-called chondrules. This figure shows three granular olive-shaped and more strip-shaped pyroxene-bearing porphyry chondrules and one radial pyroxene chondrule (bottom right). Olivine and pyroxene are typical, widespread rock-forming minerals in igneous rocks - aluminum-containing silicates with high levels of iron and magnesium. Polarizing microscope images with crossed polarizers.
The cut: After that, the origin of 'Blaubeuren' was obvious
Image 4/8, Credit: Gabriele Heinlein

The cut: After that, the origin of 'Blaubeuren' was obvious

The main piece of the 'Blaubeuren' meteorite, which weighs more than 30 kilograms and is heavily weathered on the outside, was cut in consultation with the finder in order to be able to examine the chondritic structure of the meteorite and its inclusions more closely. For this purpose, 'Blaubeuren' was brought to the specialist workshop of the Allgäu master stonemason and sculptor Peter Fraefel in Mindelheim. After intensive planning and preliminary discussions, a corner of the meteorite weighing 576 grams was sawed off on May 30, 2020.
Laser-guided stone saw: the 'opening' of 'Blaubeuren'
Image 5/8, Credit: Gabriele Heinlein

Laser-guided stone saw: the 'opening' of 'Blaubeuren'

The cut at the corner, which was to be cut off from the Blaubeuren meteorite with the diamond saw, was previously marked with a template and the find was then clamped into the stone saw device. A laser was then used to check once again in the cutting plane whether the position of the meteorite was really as desired, before the diamond saw cut through the 'Blaubeuren' plane marked by the laser.
Cut surface on 'Blaubeuren' with metallic inclusions
Image 6/8, Credit: DLR / U. Charcoal burner

Cut surface on 'Blaubeuren' with metallic inclusions

The cutting of 'Blaubeuren' provided obvious evidence that the more than 30 kilograms heavy rock found in 1989 in a garden in the Swabian town of Blaubeuren is a meteorite. In addition to the typical matrix of millimeter-sized chondrules (which can be seen in the enlargement of the photo, see also microscope image), the brightly reflective cut surfaces of metallic inclusions are also characteristic of a stone meteorite: Blaubeuren contains around five to ten percent iron and nickel. The cut surface is about 13 centimeters wide.
Meteorite size comparison: 'Blaubeuren' with 'Machtenstein' and 'Cloppenburg'
Image 7/8, Credit: DLR / U. Charcoal burner

Meteorite size comparison: 'Blaubeuren' with 'Machtenstein' and 'Cloppenburg'

'Blaubeuren' is the largest and heaviest stone meteorite ever found in Germany. Its external dimensions are around 28 by 25 by 20 centimeters. In comparison, this picture shows a cast model of the meteorite 'Machtenstein' (right), which, like 'Blaubeuren', was only recognized as a meteorite decades after its discovery in the 1950s in 2014. It is named after the place where it was found in Machtenstein near Schwabhausen in Upper Bavaria and weighs 1422 grams in the original. In the foreground is the original find, weighing 142 grams, of the meteorite 'Cloppenburg', which was found in March 2017 near the town of the same name in Lower Saxony.
Observed meteorite falls and accidental meteorite finds in Germany
Image 8/8, Credit: DLR-Feuerkugeletz / Dieter Heinlein

Observed meteorite falls and accidental meteorite finds in Germany

The map on the left shows the locations, the official name and the year of discovery of 19 meteorites that were found by chance and recognized as meteorites - but whose fall was not observed. Including the 'Blaubeuren' meteorite, which fell to earth long before it was found in 1989, possibly a few centuries ago in the valley of the Blau near Blaubeuren, a picturesque, medieval town 14 kilometers west of Ulm. The map on the right shows the names and the year of fall of 33 meteorites in Germany that have been observed to fall. The 'Blaubeuren' meteorite is not included, but among other things the meteorite 'Neuschwanstein', the fall of which was observed by the DLR's meteorite tracking network in 2002 and its fall area was then geometrically reconstructed. Then three fragments of 'Neuschwanstein' could be found.
  • By chance: Chondrite weighing 30 kilograms was found.
  • The homeowner discovered the visitor from space in 1989 while building a cable trench.
  • The meteorite probably fell from the sky hundreds of years ago.
  • Focus: planetary research, meteorites, exploration of the solar system

In science, too, chance occasionally hits the craziest capers. In 1989, while digging a cable trench on his property in the Swabian town of Blaubeuren, a house owner came across a 28 x 25 x 20 centimeter stone with a spade. From a depth of half a meter he lifts it to the surface, the stone seems unusually heavy to him. The finder uses a magnet to determine that the stone contains iron. After that, the angular chunk lies in the garden for decades. The finder did not come up with the idea that it could be a visitor from space until 31 years later and reported his find to the Institute for Planetary Research of the German Aerospace Center (DLR) in January 2020. Then after the first analyzes the scientific sensation: The find is a stone meteorite - with a mass of more than 30 kilograms, the largest ever found in Germany! On July 7th, the Meteoritical Society, the international organization of meteorite researchers that documents all meteorite finds and meteorite falls worldwide, confirmed the discovery as a recognized meteorite in a bulletin. After its place of discovery, the medieval town of Blaubeuren 17 kilometers west of Ulm, the meteorite bears the official name 'Blaubeuren'.

"It is an ordinary chondrite of the type H4-5," explains Dieter Heinlein from Augsburg, meteorite specialist for the DLR Institute for Planetary Research, who coordinates the research and investigations of 'Blaubeuren' for the DLR. "The find has a mass of 30.26 kilograms, which makes it the largest stone meteorite ever found in Germany." Before 'Blaubeuren', the 'Benthullen' meteorite found not far from Oldenburg and weighing 17.25 kilograms was the record holder. The density of 'Blaubeuren' was determined to be 3.34 grams per cubic centimeter, which is due to a significant amount of iron and nickel.

Sensational find in a chain of coincidences

The story of 'Blaubeuren' is quite extraordinary. At first, the stone, which was an obstacle when digging the cable trench and simply had to be moved out of the way, was neglected. Even a professional would hardly have concluded a meteorite at the first glance at the heavily weathered chunk. Because with potential meteorites one expects a characteristic dark melting crust, caused by the abrasion during high-speed flight through the atmosphere.

Until 2015, the meteorite lay in the finder's garden - always exposed to weathering. Then the finder almost disposed of it with other debris: "Actually, the lump was already on the trailer to be taken away," he said. Fortunately, he changed his mind and since 2015 kept the stone dry in the basement of the house in a cupboard. In January 2020, the finder wanted to be certain about the nature and origin of his special stone find and contacted DLR: Professor Heike Rauer, Head of the DLR Institute of Planetary Research, and Professor Jürgen Oberst, who monitors the DLR's meteor fireball network, brokered this Finder at Dieter Heinlein in Augsburg, the meteorite expert at DLR. For potential meteorite finds, the DLR Institute maintains a website with information and a checklist for identifying meteorites, as well as a registration address for meteor sightings.

The cut meteorite revealed the secret of 'Blaubeuren'

After a phone call and sending numerous photos, the finder sent a severed fragment weighing 23.4 grams to Dieter Heinlein. After a visual inspection, the expert first guessed iron ore, but then he picked up the diamond saw and cut open the small piece - and was amazed: Dieter Heinlein saw a matrix of millimeter-sized chondrules, spheres that were typical for stone meteorites, that formed when the Solar system emerged 4.5 billion years ago and represent the basic building blocks of all planets. He also discovered typical inclusions of metals."That was the fragment of a meteorite, I was immediately pretty sure of that," was the first judgment of the DLR expert.

On February 9, 2020, the finder handed over the main chunk to DLR in trust for further investigations, such as a precise determination of the density of the material. A little later, another 410 gram fragment was found in the finder's garden. This 'bycatch' has also been intensively researched scientifically. The main piece, which weighs more than 30 kilograms and is heavily weathered on the outside, was cut in consultation with the finder in order to be able to examine the chondritic structure of the meteorite and its inclusions more closely. Even Dieter Heinlein was overwhelmed with his special tools. "Of course, I've never had such a large chunk in the laboratory!" Dieter Heinlein found a specialist company, the workshop of the Allgäu master stonemason and sculptor Peter Fraefel in Mindelheim. After intensive planning and preliminary discussions, a corner of the meteorite weighing 576 grams was sawed off. The diamond saw was set on May 30, 2020.

A journey through three laboratories: 'Blaubeuren' was analyzed

The chemical and mineralogical analysis took place - very discreetly, because Heinlein and the DLR suspected the explosiveness of the find - in three different, specialized laboratories: At the Natural History Museum in Bern, Dr. Beda Hofmann used an X-ray fluorescence spectrometer to determine the concentrations of barium and strontium isotopes, which confirmed that the stone weathered after it fell in the Swabian Jura. The research showed: 'Blaubeuren' is definitely a Swabian '.

In the rock cellar laboratory of the VKTA - Radiation Protection, Analysis & Disposal Rossendorf e. V. were supported by Dr. Detlev Degering Carried out measurements of the radioisotope content in the material of the main meteorite mass and the post-find and at the same time measured soil samples from the garden of the family who found it. In this way, the proportions of cosmogenic, terrestrial and anthropogenic (i.e. introduced by human influence) radioisotope components can be determined. The aim is to find out approximately when the meteorite fell on earth. Judging by the state of weathering, this could have happened several centuries ago; a result in this regard is still pending.

'Blaubeuren' is the result of a cosmic collision

Finally, thin sections were made at the Institute for Planetology of the Westfälische Wilhelms-Universität Münster (WWU) in order to determine the chemical, mineralogical and petrological composition of the object under the transmitted light polarization microscope. "'Blaubeuren' is obviously a so-called breccia, a rock The Blaubeuren meteorite has experienced at least one violent collision in the past. We often see that with H4 and H5 chondrites, "explains Professor Addi Bischoff. Behind this is the iron and magnesium silicate olivine, which makes up almost three quarters of the mineralogical components of the meteorite. After these investigations, 'Blaubeuren' was submitted by Kerstin Klemm from the WWU to the Nomenclature Committee of the Meteoritical Society on June 16, 2020: Just three weeks later it was recognized as a meteorite.

Meteorites play a prominent role in research into the early development of the solar system. After all, they come to earth all by themselves and 'for free'. Most of them originally come from the asteroid belt between Mars and Jupiter, before their orbit disrupted and set off on a collision course with Earth. They are entering the atmosphere at high speed. Therefore, even with heavy chunks of stone or iron, it is often only a small residue that reaches the earth as a meteorite. For now, Blaubeuren remains with the finder. It is the owner's wish that Germany's largest stone meteorite be permanently exhibited in a museum so that the public can take a look at this 'Swabian who fell from the sky'.

All important information about the institutes and facilities of the German Aerospace Center at a glance.

    Note on the use of cookies

    Cookies facilitate the provision of our services. By using our services, you consent to our use of cookies. Further information on data protection is available via the following link: Data protection