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On 30 June 1908 a space rock, probably a stony asteroid 50 to 60 metres wide, exploded in the air above the Tunguska region of Siberia and flattened about 2,000 square kilometres of forest. No impact crater has ever been found.

Siberia, 30 June 1908

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The story behind the card

The asteroid is thought to have burst 5 to 10 kilometres above the ground, so the blast knocked trees down instead of digging a hole. They fell in a vast butterfly-shaped area about 70 kilometres across, all pointing away from the centre, while some trees right below the blast stayed upright, stripped of their branches. Estimates of the energy range from 3 to 50 megatons of TNT, hundreds of times the Hiroshima bomb. The region was so remote, and Russia so shaken by war and revolution, that Leonid Kulik's expedition reached the site only in 1927. Witnesses at a trading post 65 kilometres away felt the heat. It is still the largest impact event in recorded history.

Türkçe oku
30 Haziran 1908'de, büyük olasılıkla 50–60 metre çapında taşlı bir asteroit, Sibirya'nın Tunguska bölgesi üzerinde havada patladı ve yaklaşık 2.000 kilometrekarelik ormanı yerle bir etti. Bugüne kadar hiçbir çarpma krateri bulunamadı.
Sibirya, 30 Haziran 1908

Asteroidin yerden 5–10 kilometre yükseklikte parçalandığı düşünülüyor; bu yüzden patlama çukur açmadı, ağaçları devirdi. Ağaçlar, genişliği 70 kilometreyi bulan kelebek biçimli bir alanda merkezden dışa doğru yatmıştı. Patlamanın tam altındaki bazı ağaçlar ise dalları sıyrılmış hâlde ayakta kaldı. Patlamanın gücü 3 ile 50 megaton TNT arasında tahmin ediliyor; bu, Hiroşima'ya atılan bombanın yüzlerce katı. Bölge çok ıssızdı, Rusya da savaş ve devrimle çalkalanıyordu; bu yüzden Leonid Kulik'in ekibi olay yerine ancak 1927'de ulaşabildi. 65 kilometre uzaktaki bir ticaret karakolunda bulunan tanıklar patlamanın sıcaklığını tenlerinde hissetti. Tunguska, yazılı tarihteki en büyük çarpma olayı olmayı sürdürüyor.

Sources and further reading

Background reading: Tunguska event
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