What Is The Difference Between Meteorite's & Tektites?
People often assume that tektites and meteorites are one and the same but they are not and neither are tektites a kind of meteorite. Tektites are formed by large meteorites/comets/asteroids impacting the Earth's surface and are composed mainly of the molten terrestrial rock/soil debris created by the impact itself, that has been ejected into the atmosphere and then cooled and solidified as it re-enters earth's atmosphere. Tektites therefore come from the Earth. Meteorites however, are extra-terrestrial rocks that have fallen to Earth from space. Meteorites are Space Rocks and not of this world.
TEKTITES
Formation
Tektites are small, natural glass objects formed when a meteorite impacts the earth, causing the target rock or soil to melt and be ejected into the atmosphere. This molten terrestrial debris then cools rapidly during re-entry and solidifies into glassy shapes known as "Tektites". The word tektite comes from the Greek word "tektos" which literally means "molten" and the term was coined by Austrian Geologist Franz Eduard Suess (1867-1941).
Characteristics
1. Colour and Texture: Tektites can be black, green, brown or grey and are typically have a vitreous (glassy) texture due to their rapid cooling from a molten state.
2. Shapes: They can exhibit a variety of shapes, including spherical, oval and irregular.
3. Chemical Composition: Tektites are primarily composed of silica, with a very low water content compared to terrestrial rocks. They also lack a crystalline structure which distinguishes them from other minerals.
4. Size: Sizes range from less than 1mm for microtektites to chunks 10-20 cm in width, with most being a centimeter or so in size and weighing a few grams.
Types of Tektite
There are several types of tektites, each with distinct characteristics and origins:
- Australites: Found in Australia, known for their elongated aerodynamic shapes.
- Indochinites: Located in Southeast Asia, particularly in Vietnam, Thailand, and Cambodia - usually spherical forms.
- Moldavites: Green tektites found in the Czech Republic.
- Philippinites: Tektites found in the Philippines - disc-like shapes.
- Ivory Coast Tektites: Found specifically in the Ivory Coast Region of Africa - typically irregular shapes.
Significance
Tektites provide valuable insights into the Earth's geological history and the cosmic events that shaped it. They are often associated with meteorite impacts and help us understand the effects these had on the Earth's surface.
In summary, tektites are fascinating natural glass objects formed from the intense heat and pressure of meteorite impacts offering a glimpse into both terrestrial and extraterrestrial processes.
METEORITES
Formation
Meteorites are small, natural, solid pieces of debris from objects such as comets, asteroids or meteoroids that have come from outer space and landed on the Earth's surface. When the original space object enters the atmosphere, various factors such as friction, pressure and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a fireball, also known as a shooting star. Once this object survives its passage through Earth's atmosphere and lands on its surface, it is then classified as a meteorite.
Size, Shape and Colour
Meteorites vary in size from a few millimeters across to several feet in diameter. The largest known individual meteorite, Hoba (Iron, Namibia), measured just under 9 feet (2.7 metres) wide whilst Holbrook (Chronrite, Arizona) pieces measure up to 0.39 of an inch (1 centimetre or 10mm). Meteorites are rarely round in shape. They are typically irregular, with rounded edges and the colour will vary. A newly fallen meteorite will appear black and shiny due to the presence of a “fusion crust,” created as it passed through the Earth’s atmosphere but the longer it has been on Earth, the more this fusion crust wears away, leaving the meteorite a rusty brown color.
Types of Meteorite
1. Stony Meteorites - These make up 94% of all known meteorites and are primarily composed of silicate minerals and are further divided into;
Chondrites: - These contain small spherical grains called chondrules, which are largely unaltered since their formation and are among the oldest materials in the Solar System.
Achondrites: - These lack chondrules and are formed from differentiated bodies, often resembling volcanic rocks. They can originate from asteroids, the Moon or Mars.
2. Iron Meteorites - Dense, metallic and composed mainly of iron-nickel alloys with small amounts of sulfides and carbides. They are believed to be fragments of the cores of differentiated asteroids that melted early in the Solar Systems history. They account for about 5% of all meteorites.
3. Stony-Iron Meteorites - These account for the last 1% of all meteorites and are a mixture of metal and silicate minerals. They are subdivided into;
- Pallasites: Contain olivine crystals embedded in a metallic matrix, which are often visually striking.
- Mesosiderites: Texturally mixed rocks with both silicate and metallic components that were likely formed from collisions between asteroids.
Significance
Meteorites hold significant importance for scientists as they are the remnants of the early Solar System and serve as tangible evidence of the Universe beyond Earth, and may offer clues into its formation, evolution and the secrets contained therein.
For are full range of Tektites and Meteorites please click here.