Early on the morning of 30 June 1908, the vast forest of western Siberia was illuminated by a strange apparition: an alien object streaking across the cloudless sky. White hot from its headlong plunge into the Earth’s atmosphere, the intruder exploded about 8 km above the ground, flattening trees over an area of 2000 square kilometres.
Despite the huge detonation, equivalent to a 10 megaton nuclear warhead (about 500 times the energy of the Hiroshima atomic bomb), there were few if any casualties in the sparsely populated taiga. If the Tunguska object – probably an asteroid about twice the size of a tennis court – had exploded over London or Paris, the list of casualties would have run into millions.
Fortunately, cataclysmic events caused by incoming near-earth objects (NEOs) are few and far between. Current estimates suggest that a 50 metre Tunguska-like object is likely to collide with the Earth once every 100-300 years. A 1 km object, which typically arrives every few hundred thousand years, could wipe out an entire country. An impact in the ocean would be no better, generating enormous waves (known as tsunamis) that would devastate coastal areas thousands of kilometres away.
Franco Bonacina | alfa
UNH scientists help provide first-ever views of elusive energy explosion
16.11.2018 | University of New Hampshire
NASA keeps watch over space explosions
16.11.2018 | NASA/Goddard Space Flight Center
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
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