Investigating the chemistry of C-based compounds in primitive meteorites. Panels 'a' and 'b' are TEM images of a small region (scale bars measure 1000 nm) from a carbonaceous-type chondritic meteorite (QUE 97416). Its surface was previously measured using secondary ion mass spectrometry (SIMS), which indicated that the local area of interest shown here contains anomalies in the isotopes of C and H. Using TEM, we located the sub-surface distribution of carbon using X-ray mapping (compare panel 'c' with 'a' and 'b') as well as other elements (panels 'd' through 'i'). Combining these kinds of measurements with X-ray absorption spectroscopy provided information on the molecular chemistry of the C-based material. From Bose, Zega, and Williams (2014) Earth and Planetary Science Letters 399, 128-138.