World Library  
Flag as Inappropriate
Email this Article

Total known weight

Article Id: WHEBN0018430782
Reproduction Date:

Title: Total known weight  
Author: World Heritage Encyclopedia
Language: English
Subject: Hraschina meteorite, CI chondrite, Assisi (meteorite), Łowicz (meteorite), Middlesbrough meteorite
Publisher: World Heritage Encyclopedia

Total known weight

Total known weight (TKW), also total known mass,[1][2] is a term used mainly by dealers and meteorite collectors to indicate the combined weight of all known pieces from a single named meteorite. The total known mass of a named meteorite is a fraction of the mass of the original meteoroid that entered Earth's atmosphere to produce the meteorite (also called post-atmospheric mass).

Mass and TKW

Meteoroids that produce meteorites ablate as they pass through the atmosphere and lose mass. Thus, the total mass of a meteorite fall will always be lower than that of the original meteoroid (neglecting the mass of any terrestrial oxygen added to meteorites during the formation of their fusion crust). The upper limit to the "total known mass" of a meteorite is therefore the mass of the meteorite fall.

Several factors can cause the "total known mass" of a meteorite to be less than the mass of the fall. Meteorite falls frequently occur as showers of stones (see main article), produced when the parent meteoroid fragments. Only in cases where 100% of any such fragments are recovered, could the "total known mass" be the same as the mass of the fall. As previously undiscovered fragments are found, the "total known mass" could, in principle, rise. However, this is complicated by the method by which meteorites are named. Historically (before the 1970s), every meteorite was given a simple geographical name. The total number of known meteorites was small and it was generally a simple matter to determine when a newly found fragment was "paired" to a previously discovered meteorite. When pairing could be established, the new fragment would not be given a new name, and the "total known mass" of the original meteorite would increase. But, recent discoveries of arid regions containing large concentrations of meteorites have resulted in new rules for meteorite nomenclature. In these cases, individual meteorites are numbered (again, see main article), and every newly discovered fragment receives a unique number, even if there is a strong case that the new fragment is paired with an earlier discovered meteorite. In these cases, the "total known mass" of the meteorite is fixed at the time of the find, and cannot increase.


Low TKW means less materials for scientists and collectors. The total known weight is a key factor in pricing, especially with rare meteorite types.[3]

See also


  1. ^ The British and Irish Meteorite Society, Glossary
  2. ^ Guidelines for meteorite nomenclature - Meteoritical Society - Committee on meteorite nomenclature.
  3. ^ Kevin Kichinka. The art of collecting meteorites. Pennsylvania State University, Bookmasters, 2005.

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.