An Etymological Dictionary of Astronomy and Astrophysics
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A member of a group of tiny (millimeter to centimeter) light-colored meteorites found often with → chondrules. They consist of high vaporization minerals, including → silicates and → oxides of Ca, Al, and Ti, but are quite poor in Fe. Compared to common → chondrules, which are uniformly spherical, their shapes are less regular. They appear to be 2-3 million years older than chondrules. CAI meteorites are probably the oldest solid materials to have formed in the → solar nebula.

CAI, short for → Calcium, → Aluminium, and → Inclusion; → meteorite.

A meteorite that has distinctly separated stone, metal, and glass. It is derived from a differentiated parent body and hence not primitive. The parent body accreted surrounding material until it was large enough to start melting in the middle. The denser metals sank to the center and the stones and glasses floated to the top. A differentiated meteorite made completely of metal comes from the center of a parent meteoroid which was broken apart. → undifferenciated meteorite.

Differentiated, p.p. of → differentiate; → meteorite.

The world's largest meteorite found in 1920, near Grootfontein, Namibia. It was discovered by Jacobus H. Brits while ploughing one of his fields with an ox. The meteorite is tabular in shape and measures 2.95 x 2.84 m; it has an average thickness of about 1 m (1.22 m maximum and 0.75 m minimum). The Hoba meteorite weighs about 65-70 tons. Its chemical composition is 82.4 % iron, 16.4 % nickel, 0.8 % Cobalt, and traces of other metals. No crater is present around the site of the meteorite, probably because it fell at a lower rate of speed than expected. The flat shape of the object may be responsible for its low velocity at impact.

Named after Hoba West, the farm it was discovered; → meteorite.

A meteorite which is composed mainly of iron mixed with smaller amounts of → nickel. Iron meteorites make up about 4.4% of all meteorites. See also → stony meteorite, → stony-iron meteorite.

→ iron; → meteorite.

The biggest meteorite ever witnessed falling and the largest stone meteorite known. It happened near Jilin, an industrial port city located northeastern China, on March 8, 1976. Of the four tons of fragments of the type H5 chondrite recovered, one piece weighs 1.774 tons and measures about 100 x 80 x 50 cm. The meteorite exploded in the sky and produced a shower covering an area of more than 500 square kilometers.

Jilin, from the name of the Chinese city, known also as Chi-lin City or Kirin City. → meteorite.

A piece of rock that was ejected from the Martian surface into space by the impact of an asteroid or comet, and landed on Earth. So far about 100 Martian meteorites have been collected. These meteorites have elemental and isotopic compositions that match those of the Martian crust as measured by NASA's Mars exploration missions.

→ Martian; → meteorite.

An object of → extraterrestrial origin that survives entry through the atmosphere to reach the Earth's surface. → Meteors become meteorites if they reach the ground. See also → stony meteorite, → iron meteorite, → stony-iron meteorite, → chondrite, → micrometeorite , → achondrite, → CAI meteorite, → differentiated meteorite, → undifferentiated meteorite, → Hoba meteorite, → Jilin meteorite, → Martian meteorite, → meteorite flux.

From → meteor + -ite a suffix of nouns.

Šaxâné "metor," may be from šaxudan, šaxânidan "to scratch, to thrust, to assail," as the meteor light scratches the dark night.
Šahâbsang, from šahâb, → meteor, + sang, → stone.
Âsmânsang, from âsmân, → sky, + sang, → stone.

The total mass of extraterrestrial objects that land on Earth during a given time period. The meteorite flux is currently estimated to be about 10⁷ to 10⁹ kg yr^-1. Much of this material is dust-sized objects called → micrometeorites.

→ meteorite; → flux.

A small grain sized meteorite which can only be positively identified under the microscope.

→ micro-; → meteorite.

A meteorite composed largely of rock-forming (→ silicate) → minerals. Stony meteorites are the most abundant kind, about 95%, of all meteorites. They are divided into two groups: → chondrites and → achondrites.

→ stone; → meteorite.

Meteorites comprised of roughly equal amounts of → nickel/→ iron and → stone. They are divided into two groups: → pallasites and → mesosiderites. The stony-irons are thought to have formed at the core/mantle boundary of their parent bodies. The stony-irons account for less than 2% of all known meteorites. Also called → siderolite.

→ stony; → iron; → meteorite.

A type of meteorite in which the constituting materials (stone, glass, metal) are mixed together in a disorderly mass, in contrast to → differentiated meteorites.

→ un-; → differentiated meteorite.