A study led by the University of Kent’s Faculty of Physical Sciences has found new evidence of a low-altitude meteorite touchdown event that reached the Antarctic ice sheet 430,000 years ago.
A research team of international space scientists, led by Dr. Matthias van Ginneken of the Center for Astronomical and Planetary Sciences, Faculty of Physical Sciences, has discovered new evidence of a low-altitude meteorite touchdown event that reached the Antarctic ice sheet 430,000 years ago.
Extraterrestrial particles (condensed spheres) recovered at the top of the Wolnam Fieretto (WN) in the Sør Rondane Mountains, Queen Maud Land, East Antarctica, generate a jet of molten and vaporized meteorite material due to atmospheric entry. Indicates an unusual touchdown event. Asteroids at least 100 meters in size reached the surface at high speed.
This type of explosion caused by the collision of a single asteroid is called intermediate because it is larger than an air burst but smaller than a collision crater event.
The bulk measure of chondrites, the chemistry of trace elements, and the high nickel content of the debris indicate the extraterrestrial properties of the recovered particles. Their unique oxygen isotopic signatures indicate that they interacted with oxygen from the Antarctic ice sheet during formation in the impact plume.
The findings show far more dangerous consequences than the 1908 and 2013 Tunguska and Chelyabinsk events in Russia, respectively.
This study Science AdvancesLeads to an important discovery of geological records lacking evidence of such events. This is mainly due to the difficulty in identifying and characterizing impact particles.
This study emphasizes the importance of reassessing the threat of medium-sized asteroids, as similar touchdown events are likely to produce similar particles. Such an event is completely destructive over a large area, corresponding to the area of interaction between the hot jet and the ground.
Dr. van Ginneken said: surface. Our research may also help identify these events in the deep-sea sediment core and record sedimentation when plume expansion reaches the land mass.
“If a touchdown event occurs over Antarctica, it may not threaten human activity, but if it occurs over densely populated areas, millions of people can reach distances of up to hundreds of kilometers. There will be casualties and serious damage. “
The extraterrestrial particles (condensed spheres) examined in this study are based at the Elizabeth Antarctic Station in Belgium and are funded by the Belgian Science Policy (Belspo) during the 2017-2018 Belgian Antarctic Meteorite (BELAM) expedition. Found inside.
Reference: “A large-scale meteorite event in Antarctica. Inferred from the chondrite spheres of the Sør Rondane Mountains before 430 ka,” M. Van Ginneken, S. Goderis, N. Artemieva, V. Debaille, S. Decrée, RP Harvey, KA Huwig, L. Hecht, S. Yang, Fed Kaufman, B. Thorns, M. Humayun, F. Van Mardegem, MJ Genge, P.Craze, March 31, 2021 Science Advances..
DOI: 10.1126 / sciadv.abc1008
Extraterrestrial particles found in Antarctica reveal the effects of ancient meteorites 430,000 years ago
https://scitechdaily.com/extra-terrestrial-particles-discovered-in-antarctica-reveal-ancient-meteoritic-impact-430000-years-ago/ Extraterrestrial particles found in Antarctica reveal the effects of ancient meteorites 430,000 years ago