. | . |
Twelfth impact structure discovered in Central Finland by Staff Writers Helsinki, Finland (SPX) Jun 28, 2018
The crater has a diameter of 2.6 km and it is covered by the Lake Summasjarvi (Summanen), about 9 km south-east of the nearest city, Saarijarvi, and 275 km north of Helsinki. The age of the impact event and the type of the meteorite causing the crater, are still unknown. The discovery is based on earlier geophysical studies of the area by Geological Survey of Finland. As a consequence of the field trip conducted by the Finnish-Estonian research team in 2017, proofs of an ancient asteroidal shock were obtained. Researchers found shatter cones, fractured and brecciated rocks in Summanen area The Summanen geophysical feature was first identified in the early 2000's by Jouko Vanne, a geologist at the Geological Survey of Finland. The observation was based on low altitude aeroelectromagnetic data that revealed circular electromagnetic apparent resistivity anomaly associated with Lake Summanen. The meteorite impact theory got a further kick in summer of 2017, when the Finnish-Estonian team found inevitable evidences of traces of a meteorite hit. In particular, shatter cones, fractured and brecciated rocks were discovered in Summanen area. The microscope studies of thin sections of shocked rocks prove the meteorite impact interpretation and reveal huge shock pressures suffered by the local basement rocks. In time of the crater formation, the diameter has been larger compared to the present 2.6 km since the erosion by geological processes, augmented by glaciations, have diminished the original crater size. There are now 191 confirmed meteorite impact structures on Earth Summanen is 191st confirmed meteorite impact structure on the surface of planet Earth. The great majority is found on continental areas with only a few oceanic impacts. Although in global perspective the Summanen belongs to the group of small craters, it, together with the eleven previously proven impact structures in Finland, places Finland into one of the leading countries to find impact structures. The largest impact structure in Finland, the Keurusselka structure locating also in Central Finland, has a diameter of >30 km with an age of about 1100 million years. The Summanen explosion has been much smaller, but, nevertheless, produced a big damage in the environment.
Research Report: Summanen, a new meteorite impact structure in Central Finland
Earth's first mission to a binary asteroid, for planetary defence Paris (ESA) Jun 26, 2018 Planning for humankind's first mission to a binary asteroid system has entered its next engineering phase. ESA's proposed Hera mission would also be Europe's contribution to an ambitious planetary defence experiment. Named for the Greek goddess of marriage, Hera would fly to the Didymos pair of Near-Earth asteroids: the 780 m-diameter mountain-sized main body is orbited by a 160 m moon, informally called 'Didymoon', about the same size as the Great Pyramid of Giza. "Such a binary asteroid sy ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |