After 54 Years, a Mysterious Rock Identified as a One-Kilo Meteorite!

An investigation worthy of a great thriller, which shows how important old data can be.

[Cet article a initialement été publié le 24 juin 2024]

Are meteor showers every day?

As explained by Bernard Melguen, author of Meteorites, messengers of space during an interview for France Info, each year it would fall between “100,000 to 200,000 tons of meteorites” on Earth. Therefore, it would rain daily.

However, “90% of these meteorites, including shooting stars, are very small fragments, sometimes only a few millimeters in size.”, specifies the astronomy specialist. Moreover, the difficulty lies in finding and authenticating them.

Good intuition, thirty-two years later

Proof of this comes from this anecdote dating from 1976 where Josef Pfefferle, a forester in the Austrian Alps, discovered a strange stone the size of a fist while clearing the remains of an avalanche near the Austrian village of Ischgl. Fascinated by her uniqueness, he decides to take her home and put her in a box.

Thirty-two years later, Josef Pfefferle watched a television report discussing a meteorite discovered in Austria. The forest ranger then thinks back to his strange stone picked up several decades ago in the forest and decides to find out for sure, by bringing his loot to a University so that it can be analyzed.

Apparently blessed with good intuition, it was thanks to this initiative by Josef Pfefferle that the researchers ended up with a meteorite weighing around one kilo, or relatively large. “It was such a fresh meteorite, and extremely well preserved” Maria Gritsevich of the University of Helsinki (Finland) and planetary scientist, who led the study of the rock fragment, told the New York Times. The meteorite would have indeed landed on Earth shortly before being picked up, according to analyses.

Find the identity of the meteorite using precise archives

Since 1966, no less than 25 cameras located in southern Germany have been filming the night sky. Scientists therefore studied its images, preserved by the German Aerospace Center in Augsburg, to determine precisely which meteorite it could be.

Taking into account where the Ischgl meteorite was found, Maria Gritsevich and her colleagues hypothesized that it came from a fireball that entered the Earth's atmosphere on the morning of November 24, 1970.

However, as Peter Brown, a planetary scientist at Western University in Ontario (who was not involved in the research), explains to the New York Times, this famous meteorite could just as easily be even older. Its freshness would come from the alpine environment in which it fell, which could have preserved the rock. “”It could have remained there for decades, even centuries.”