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Basic information Name: Towada
     This is an OFFICIAL meteorite name.
Abbreviation: There is no official abbreviation for this meteorite.
Observed fall: No
Year found: 1997
Country: Japan
Mass:help 53.5 g
NHM Catalogue:  5th Edition  (2000)  H6
Meteoritical Bulletin:  MB 86  (2002)  H6
MetBase:  v. 7.1  (2006)  H6
Recommended:  H6    [explanation]

This is 1 of 6726 approved meteorites (plus 6 unapproved names) classified as H6.   [show all]
Search for other: H chondrites, H chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7)
Writeup from MB 86:


Aomori, Japan

Found 1997 late April

Ordinary chondrite (H6)

A stone of 53.5 g was found outside a barn, beneath a hole in the eaves, by Mr. K. Ishikura.  The meteorite probably fell between 1985, when the barn was built, and 1992, based on 22Na abundance being below detection (S. Yoneda, NSMT). Mineralogy (A. Okada, RIKEN; S. Yoneda, NSMT): olivine, Fa19–20; pyroxene, Fs17–19; CaO, 0.6–0.9%; slightly weathered. Chemistry (Y. Oura and M. Ebihara, TMU): CI­and Si-normalised, Al = 1.03, Sc = 0.97, Ca = 0.88, Na = 0.79, As = 0.62, S = 0.21, Ir = 0.94, Co = 1.10, Au = 0.94. Oxygen isotopes (M. Kusakabe, OkaU): δ17O = +2.64 to +2.94‰, δ18O = +3.85 to +4.22‰. Cosmogenic nuclides (J. Park, R. Okazaki and K. Nagao, UTok): 21Ne exposure age = 31 Ma. Specimens: type specimen, 9 g (8.5 g remaining), NSMT; main mass property of the finder and on long-term loan to Towada City Cultural Center.

Plots: O isotopes:  
   and collections
UTok: University Museum, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan (institutional address; updated 3 Oct 2021)
OkaU: Institute for Study of the Earth's Interior, Okayama University, Misasa Tottori 682-0193, Japan (institutional address)
RIKEN: Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako Saitama 351-0198, Japan (institutional address)
TMU: Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji-shi, Tokyo 192-0397, Japan (institutional address)
NSMT: National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba, Ibaraki 305-0005, JAPAN, Japan; Website (institutional address; updated 16 Jun 2014)
References: Published in Meteoritical Bulletin, no. 86, MAPS 37, A157-A184 (2002)
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Photos from the Encyclopedia of Meteorites:
Yasuo Shiba      

     Catalogue of Meteorites:   (40° 33'N, 141° 14'E)
     Recommended::   (40° 33'N, 141° 14'E)

     This is 1 of 12 approved meteorites from Tohoku, Japan (plus 1 unapproved name)
     This is 1 of 58 approved meteorites from Japan (plus 12 unapproved names)
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