History...
On the 3rd October 1962 a farmer in the Katsina Province of Nigeria was tending his field when he witnessed the fall of a single 40lb black rock, impacting the ground just 10ft from him and creating a hole 2ft deep. The fall was accompanied by a loud sonic boom which was heard pver several miles away, and a smoke trail which remained in the sky for several minutes. The alarm was raised and local officials were soon on the scene, retrieved the rock and took it to the local museum. As the scientific community were informed, investigation and analysis soon started, and a whole new chapter of meteoritics was about to the written.....
With a very young crystallization age of just 1,300 million years old, as opposed to the normal 4,600 million years old of other meteorites, the Zagami Meteorite bewildered scientists. International effort later matched it to another bizarre and bewildering meteorite that had fallen in Shergotty, India on the 25th August 1865. The Shergotty meteorite was unlike any other meteorite known and so gave birth to its own scientific classification termed "Shergottites". Since the Zagami meteorite exhibited similar properties it was classified as a Shergottite stone meteorite although no-one was really any wiser about these enigmatic meteorites.
Further international efforts found two other meteorites which shared a similar age and composition. Firstly was the Nakhla meteorite which fell as a shower of stones in Egypt on the 28th June 1911. Secondly there was the Chassigny meteorite whic had fallen in France in 1815. Although separate classifications had been created for all these meteorites; termed "Shergottites", "Nakhlites" and "Chassignites", they all displayed striking similarities and soon became collectively known as the "SNC" meteorites.
After much research, debate, criticism, more research, experiments, investigations, geological field work and an interplanetary space mission, the SNC Meteorites are now known to be of Martian origin; in they originated from the planet Mars.
This was originally proposed because their young crystallization structure and age of just 1,300 million years old suggested that they were formed within a gravitational field stronger than that of the largest asteroids. It was later discovered that their chemical composition closely matched that of the Martian atmosphere. Final and conclusive confirmation came during the late 1970's when the NASA Viking landers touched down on the surface of Mars, commencing an array of scientific geological experiments and beaming the results back to Earth. They reported striking similarities with the SNC Meteorites.
Modern research, computer simulations and the 1997 NASA Pathfinder mission to Mars have further confirmed the SNC's Martian origin. These rocks reached Earth after a tremendous impact on the surface of Mars causing material to be ejected with escape velocity to break free of the Martian gravity and be sent out into space on an eventual collision coarse with Earth. The Tharsis crater measuring 34x18km is believed to be the parent crater for all the SNC Meteorites.
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