Tagish Lake meteorite

TABLE 5.3 The Organic Content of the Tagish Lake Meteorite... 

SOURCE Data from Pizzarello, S., Huang, Y.S., Becker, L., Poreda, R.J., Nieman, R.A., Cooper, G., and Williams, M. 2001. The organic content of the Tagish Lake meteorite. Science 293 2236. 

Tagish Lake (meteorite) A unique carbonaceous chondrite collected very soon after falling to Earth in a remote part of northwestern Canada in January 2001... 

Hiroi T., Zolensky M. E., and Pieters C. M. (2001) The Tagish Lake meteorite a possible sample from a D-type asteroid. Science 293, 2234-2236. 

Brown PG, Hildebrand AR, Zolensky ME, Grady M, Clayton RN, Mayeda TK, Tagliaferri E, Spalding R, MacRae ND, Hffman EL, Mittlefehldt DW, Wacker JF, Bird JA, Campbell MD, Carpenter R, Gingerich H, Glatiotis M, Greiner E, Mazur MJ, McCausland PJ, Plotkin H, Mazur TR (2000) The fall, recovery, orbit,and composition of the Tagish Lake meteorite A new type of carbonaceous chondrite. Science 290 320-325... 

Table 2.5 Water soluble organic compounds (WSOC) in the Tagish Lake meteorite, fell in January 2000 in Canada, after Pizzarello et al. (2001) - the first pristine carbonaceous chon-drite found on earth.

Fig. 11 SEM images of magnetite (Fe304) colloidal crystals in the Tagish Lake meteorite. The morphology is inset at the upper right in each image, (a) Colloidal crystal with the bet structure composed of octahedral, crystalline nanoparticles of Fc304 bounded by 111 faces, (b) Colloidal crystal with the fee structure. The morphology of theconstituent particles is rhombic-dodecahedral, bounded only by 110 faces, (c) Colloidal crystal with the fee structure composed of particles bounded by 100, 110, and 311 faces. Reprinted with permission from the American Chemical Society. ...

Especially large amounts of the uncontaminated CM chondrites Murchison and Tagish Lake have been available since their falls in 1969 and 2000, respectively, and most modem research on extraterrestrial organic matter has focused on these meteorites. Considerable research has also been done on organic matter in the Orgueil Cl chondrite, but this meteorite has been contaminated during its nearly 150 years on Earth. 

We do not know the extent to which the Murchison organics reflect what was available on early Earth before life emerged. The rich inventory of amino acids does not appear to be universal in carbonaceous chondrites (although the number that have been examined in detail is very small). For example, only a few amino acids (glycine, alanine, a-aminoisobutyric acid, a-amino-n-butyric acid, y-aminobutyric acid) are found in the meteorite that fell in 2000 on Tagish Lake, Canada (Table 5.3).7 The near absence of complex amino acids is significant, inasmuch as the meteorite was captured in a pristine condition soon after it fell. 

Zolensky M. E., Nakamura K., Gounelle M., Mikouchi T., Kasama T., Tachikawa O., and Tonui E. (2002) Mineralogy of Tagish Lake an ungrouped type 2 carbonaceous chondrite. Meteorit. Planet. Sci. 37, 737-761. 

Table 5 Carbon isotope compositions of CO, CO2, carboxybc acids, dicarboxylic acids, and volatile hydrocarbons in the Murchison (CM2), Tagish Lake (Cl), and Orgueil (CIl) meteorites together with hydrogen isotope...

Spectral reflectances of some meteorites match those of some asteroid types irons or E chondrites with M type enstatite achondrites with E type the unique carbonaceous chondrite Tagish Lake with D type HED achondrites with V type stony-irons with most S type thermally metamorphosed carbonaceous chondrites (see below) with C, G, B and F types. (Relative... 

A low concentration of nitrogen and sulfur heterocycles also can be found in various petroleums. Coal was for years the major source of pyridine-based heterocycles, obtained by pyrolysis in the absence of oxygen (destmctive distillation). An intriguing new detection of heterocycles in nature has occurred in the field of chemistry of the solar system. Pyridine carboxylic acids have been detected in a meteorite that landed in Canada (near Tagish Lake)." Nicotinic acid and its two isomers were isolated along with 12 methylated and other derivatives. 

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