Nakhla meteorite

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The Nakhla meteorite, the first example of a Nakhlite type meteorite of the SNC Group type of meteorites, fell to Earth, from Mars, on the 28th of June, 1911, at approximately 09:00 in the Nakhla region of Abu Hommos, Alexandria, Egypt.^[1][2] The meteorite fell in about forty pieces and was witnessed by many individuals to have exploded in the upper atmosphere and to have fallen into the ground, the fragments burying themselves up to a meter in depth in some places. The stones recovered from this meteorite ranged in size from 20g to 1813g, and it is estimated a total weight of 10kg (22 pounds) had fallen.^[1]

Martian origins

As of 2008, there are a total of seventy-seven cataloged meteorites recovered from around the world that are thought to have originated from Mars,^[3] including the Nakhla meteorite. These are considered to have been ejected by the impact of another large body colliding with the Martian surface and traveled through the solar system for an unknown period of time before penetrating the Earth's atmosphere.

Examination of the Nakhla meteorite in March 1999, using an optical microscope and a powerful scanning electron microscope (SEM), by a team from NASA's Johnson Space Center, has revealed rounded particles of a limited size range.^[4] London's Natural History Museum, which holds several intact fragments of the meteorite, agreed on 2006 for NASA researchers to break one open, providing fresh samples.^[5] Upon publishing the results, a debate was opened by some at the 37th Lunar and Planetary Science Conference in March 2006 in Houston, Texas, and postulated that the carbon-rich content within the pores of the rocks hinted at remains of living matter.

Because Carbon is the fourth most abundant element in the universe after hydrogen, helium, and oxygen, most scientists, curious and minute shapes in meteorites are not enough to convince them that bacteria once lived on Mars.^[6]

The Nakhla dog

One such fragment of the Nakhla meteorite was said to be observed by a farmer named Mohammed Ali Effendi Hakim in the village of Denshal, near Nakhla, to have landed, not only in his field, but on a dog and, apparently, vaporized the animal. Since, therefore, no remains of the dog were ever recovered and only one known eyewitness to the dog's death is known, this story remains apocryphal at best.^[1] However, the story of the Nakhla dog has become something of a legend among astronomers and is even recorded in several editions of The Catalog of Meteorites.

At the time, the dog's death publicized in both Arabic and English newspapers as being the first recorded death of an animal, including humans, by a meteorite, though since then both the facts as to whether a dog was actually killed by meteorite in Nakhla and the notion that this was the first ever recorded animal fatality by meteorite have come into question.