Last week a team of Russian scientists published a new paper titled “Tunguska cosmic body of 1908: is it from planet Mars?” The authors analysed various remnants in the Siberian area of the severe explosion observed back in June 30, 1908 to find any possible relation between the cause of this disaster and one of its hypothetical sources, the Red Planet.
The paper is available at arXiv.org.
The exact origin of Tunguska meteorite is still mostly a mystery, although more than 100 years have passed since the event. Apparently, the explosion was caused by a space object, which had entered Earth’s atmosphere at a hypersonic velocity. Since then there have been many claims regarding the discovery of interesting and sometimes ‘strange’ objects that could have formed in the aftermath. However, most of these reports either have not been verified, or the evidence was lost before any significant chemical analysis could be accomplished.
This situation started to change during the recent years. In 2013 Russian scientist Andrey Zlobin has published a paper, in which he claimed to have found some pebbles – remnants from the Tunguska meteor. He described the chemical composition of those potential remnants from the explosion in the paper and noted that one of the specimens consisted of “quartz-like” substance with the visible traces of melting on the surface.
The authors of the current study note that the finding described by Andrey Zlobin is interesting due to the fact that the quartz-containing rocks have been recently identified on Mars, whereas this mineral is rarely found in meteorites here on Earth. The researchers note that this argument was the main cause to consider Mars as a potential origin of the Tunguska meteorite.
The team surveyed the results of the previous studies on this phenomenon, including the eyewitness’ reports from that time and subsequent excavations, as well as aerial photos of the location. This data was used to reconstruct the patterns and positions of the rock shards and pebbles that originally belonged to to a larger boulder discovered in July 19, 1972, known under the name John’s Stone.
Some of the available specimens of the shear-fractured splinter fragments of the John’s Stone contain glassy coatings that indicate the effect of heat generated during the meteorite impact. The team performed an experiment to reproduce the same crystalline structure on another rock fragment obtained from the John’s Stone. Sadly, this experiment was not successful: the specimen disintegrated after heating by a 5000 K plasma beam.
Despite this failure, the authors claim that, most likely, the John’s Stone is not of the local origin, although it shares some similarities with other rocks found in this area. The claim is supported by the analysis of its mineral structure, chemical composition of the rock, surrounding soil layers density, abundance and positions of the surrounding splinters with glassy coatings. Also, the reconstructed trajectory and landing velocity of the John’s Stone agrees well with the estimated trajectory of the Tunguska cosmic body flight.
The team notes that the results of the current study – in particular, the hypothesis about the Martian origin of John’s Stone – should be verified further by an independent international interdisciplinary research group.
By Alius Noreika, Source: www.technology.org