Tasmanite (tektite)
Among the general part of tasmanites belonging to the southern branch of australites, there are varieties of regular “aerodynamic" shape (sometimes in the form of a small bowl), disc-shaped or hollow balls.
[5] After the completion of the colonization of Australia, this circumstance attracted increased attention to them, making them an object of collecting and souvenir sale, and, starting from the mid-19th century, of professional study.
[6]In January–February 1836, during his voyage around the world on the Beagle, Charles Darwin personally collected tektite samples during stops in South Australia and Tasmania.
[2] When the Beagle dropped anchor off the coast of Tasmania, Darwin, setting off on another excursion inland, unexpectedly discovered on the ground hollow balls of black glass, little larger than a walnut.
[8]: 12 Considering black glasses to be a purely geological object formed in the bowels of the earth, Darwin characterized them as a kind of "volcanic bomb", thrown out from the craters of volcanoes during an eruption.
[11] Important studies that sharply increased the interest of the scientific community in tektites were the generalizing theoretical works of the Austrian geologist, Professor Eduard Suess.
Using the example of the only European tektites, which were Czech fossil glasses, Suess, without chemical analysis, came to the conclusion that they were of cosmic origin and were not related to the surrounding geological rocks.
[14] Almost all assumptions and scientific conclusions made regarding australite-indochinites are directly related to tasmanites, the main part of which belongs to a single Australo-Tasmanian dispersion arc, and only isolated southwestern tektites from the Darwin Crater are of purely local origin.
[5] A new hypothesis about the origin of australites arose in the late 1960s based on data received from the American Surveyor 7 spacecraft, which landed in 1968 near the Tycho crater.
Professor D. Chapman of the Ames Research Center (Mountain View, California) was able to prove using computer programming that only the stream of glass splashes ejected from the Tycho crater during the eruption, combined with the rotation of the Earth, could create a scattering streak such an unusual shape.
They traditionally endowed local tektites with magical properties and called them "moon stones", as if in the foreseeable legendary times their ancestors were contemporaries and witnesses of their "fall from the sky."
Regarding radiation measurements, selenologists for a long time could not develop a consensus; chronological estimates had an incredibly inflated appearance, as if the real picture was deliberately distorted by some unaccounted for factor or unknown to modern science.
Australites most likely received their streamlined aerodynamic shapes during the secondary re-entry of debris into the Earth's atmosphere, when pieces of glass in a molten state flew at high speed.
Half a century later, in 2006–2009 in Antarctica (Wilkes Land), according to the results of satellite research, a huge crater hidden under a deep layer of ice, a trace of one of the largest meteorite collisions with the Earth, was discovered in practice.
During the experiments, it was possible to reproduce in the smallest detail almost all existing forms of australites, including the disk-shaped one, and to obtain the aerodynamic relief of the rings on the front surface.
[18] Judging by their similar age and composition,[19] the Australites belong to the southern margin of the largest known Australasian scatter field, extending from Indochina (indochinites) to Tasmania (tasmanites, Darwin glass).
A number of studies of "flange"-shaped samples have shown that exactly such an aerodynamic profile can be obtained from an initial glass sphere invading the earth's atmosphere at cosmic speed.
The greatest difficulty in modeling the situation is the need to distinguish between the effects of terrestrial and cosmic factors, since the surface structure of tektites sometimes seems too complex.
