#chondrites

Meteorites are natural objects made of iron & stone which fall from space through the Earth’s atmosphere.  Their size ranges from dust-sized particles to huge lumps weighing many tonnes.

Meteorites have been falling throughout the Earth’s history.  They are very important, as they record the Solar System’s birth (4,560 million years ago), and its subsequent history.

The first written records of meteorites are in cuneiform, about 1900 BC.  A decade or two ago, fossilized meteorites that fell to Earth over 450 million years ago were recently found in Sweden.

Meteorites are made up of the same elements as the Earth & Sun.  These elements combine to form over 300 different minerals - some of these minerals are not found on Earth.

The abundance & types of minerals in the meteorites are used to classify them into three categories: stones (chondrites & achondrites), stony-irons (e.g. pallasites), and irons.

As a response to a previous post that mentioned continent formation, I said I should do a post on continent formation. But there is an interesting issue relating to how to form a theory, and it is, if you want to go from A to B, in this case going from a non-descript planet to one with continents and oceans, sometimes it is helpful to start by focussing on C. When I wrote my “Planetary Formation…

Where Did Earth’s Water Come From? Study Casts Doubt on The Current Meteorite Theory

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Water covers 70 percent of the Earth’s surface and is crucial to life as we know it, but how it got here has been a longstanding scientific debate.

The puzzle was a step closer to being solved Thursday after a French team reported in the journal Science they had identified which space rocks were responsible, and suggested our planet has been wet ever since it formed.

  Cosmochemist…

Meteorites may have come from small worlds with lava oceans in the early solar system- Technology News, Firstpost

The New York TimesJun 23, 2020 11:38:17 IST

“Droplets of fiery rain.”

That’s how Henry Clifton Sorby, a 19th-century British mineralogist, described the tiny spheres referred to as chondrules discovered inside meteorites. Chondrules are such dominant options of those meteorites that they’re referred to as chondrites, they usually account for 86% of meteorites which have been discovered on…

Meteorites may have come from small worlds with lava oceans in the early solar system- Technology News, Firstpost

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The New York TimesJun 23, 2020 10:08:44 IST

“Droplets of fiery rain.”

That’s how Henry Clifton Sorby, a 19th-century British mineralogist, described the tiny spheres called chondrules found within meteorites. Chondrules are such dominant features of these meteorites that they are called chondrites, and they account for 86% of meteorites that have been found on Earth.

Their origin,…

Meteorites Rained Cyanide on Early Earth, And It May Have Helped Kickstart Life

If you swallow a bunch of cyanide or breathe in too much carbon monoxide, you are in for a pretty bad time, since both are poisonous to humans. But they may have been instrumental to our very existence – and new evidence suggests both were carried here on meteorites.  

In a type of carbon-rich meteorite called carbonaceous chondrites, which bombarded our planet prior to the emergence of life,…