Stagnation region flow-field of ablating meteoroid. In the frontal region of a meteoroid flying through the atmosphere, two distinct layers of gaseous state form behind the bow shock wave, one by air (shock layer) in the outer region and the other by the ablation-product (ablation layer) in the inner region. The quantities flowing axially are denoted with dots, that is, Ṁ and Q̇, and are per area per sec. The quantities flowing radially are denoted without dots, that is M and Q, and are per sec.