Pultusk (meteorite)
Encyclopedia
Pultusk is an H5 ordinary chondrite
meteorite
fallen on January 30, 1868 in Poland
.
. Thousands of people witnessed a large fireball followed by detonations and a very large shower of small fragments falling on ice, land and houses within an area of about 127 sq km. The estimated number of fragments was 68780. The fragments ranged in weight from half a gram to 9.095 kg (the largest specimen). The overall estimated mass of the meteorites was 8,863 kg. The vast majority of the fragments were small (few grams) and are known as Pultusk Peas. The Pultusk meteorite is one of the largest stony meteorite shower recorded in history.
s embedded in a dark brecciated matrix.
The meteorite Pultusk is a veined and brecciated chondrite
with abundant xenolith
s with various degrees of recrystallisation. Petrologic type 5 xenoliths prevail, so it has been classified as H5
: an ordinary chondrite significantly thermally metamorphosed and with the contours of the chondrule
s frequently difficult to distinguish.
The main minerals are olivine
and bronzite
. Kamacite
, troilite
and chromite
are also present.
H chondrite
The H type ordinary chondrites are the most common type of meteorite, accounting for approximately 40% of all those catalogued, 46% of the ordinary chondrites, and 44% of the chondrites....
meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
fallen on January 30, 1868 in Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
.
History
The fall occurred on January 30, 1868 at 7 pm near the town of Pułtusk, about 60 km northeast of WarsawWarsaw
Warsaw is the capital and largest city of Poland. It is located on the Vistula River, roughly from the Baltic Sea and from the Carpathian Mountains. Its population in 2010 was estimated at 1,716,855 residents with a greater metropolitan area of 2,631,902 residents, making Warsaw the 10th most...
. Thousands of people witnessed a large fireball followed by detonations and a very large shower of small fragments falling on ice, land and houses within an area of about 127 sq km. The estimated number of fragments was 68780. The fragments ranged in weight from half a gram to 9.095 kg (the largest specimen). The overall estimated mass of the meteorites was 8,863 kg. The vast majority of the fragments were small (few grams) and are known as Pultusk Peas. The Pultusk meteorite is one of the largest stony meteorite shower recorded in history.
Composition and classification
Pultusk is brecciated and contains two varieties of xenolithXenolith
A xenolith is a rock fragment which becomes enveloped in a larger rock during the latter's development and hardening. In geology, the term xenolith is almost exclusively used to describe inclusions in igneous rock during magma emplacement and eruption...
s embedded in a dark brecciated matrix.
The meteorite Pultusk is a veined and brecciated chondrite
Chondrite
Chondrites are stony meteorites that have not been modified due to melting or differentiation of the parent body. They formed when various types of dust and small grains that were present in the early solar system accreted to form primitive asteroids...
with abundant xenolith
Xenolith
A xenolith is a rock fragment which becomes enveloped in a larger rock during the latter's development and hardening. In geology, the term xenolith is almost exclusively used to describe inclusions in igneous rock during magma emplacement and eruption...
s with various degrees of recrystallisation. Petrologic type 5 xenoliths prevail, so it has been classified as H5
H chondrite
The H type ordinary chondrites are the most common type of meteorite, accounting for approximately 40% of all those catalogued, 46% of the ordinary chondrites, and 44% of the chondrites....
: an ordinary chondrite significantly thermally metamorphosed and with the contours of the chondrule
Chondrule
Chondrules are round grains found in chondrites. Chondrules form as molten or partially molten droplets in space before being accreted to their parent asteroids...
s frequently difficult to distinguish.
The main minerals are olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....
and bronzite
Bronzite
Bronzite is a member of the orthopyroxene group of minerals, belonging with enstatite and hypersthene to the orthorhombic series of the group...
. Kamacite
Kamacite
Kamacite is a mineral. It is an alloy of iron and nickel, usually in the proportions of 90:10 to 95:5 although impurities such as cobalt or carbon may be present. On the surface of Earth, it occurs naturally only in meteorites. It has a metallic luster, is gray and has no clear cleavage although...
, troilite
Troilite
Troilite is a rare iron sulfide mineral with the simple formula of FeS. It is the iron rich endmember of the pyrrhotite group. Pyrrhotite has the formula FeS which is iron deficient...
and chromite
Chromite
Chromite is an iron chromium oxide: FeCr2O4. It is an oxide mineral belonging to the spinel group. Magnesium can substitute for iron in variable amounts as it forms a solid solution with magnesiochromite ; substitution of aluminium occurs leading to hercynite .-Occurrence:Chromite is found in...
are also present.