In hypersonics particularly, the interest in carbon species arises from the use of ablating carbonaceous heat shields. Returning spacecrafts can attain entry speeds of 10-13 km/s which results in intense radiation in the shock layer that is directed towards the spacecraft fore body. The radiation is predominantly due to atomic N(I) and O(I) lines with the main spectral feature being the intense 174.29 nm line of atomic nitrogen. Ablating heat shields undergo pyrolysis and sublimation resulting in the formation of a gas layer which carries away some of the incident radiation via convention thereby mitigating the radiative heat flux on the spacecraft. Another source of radiation attenuation is by absorption of a portion of the incoming radiative heat flux from the shocked gases by the pyrolysis gases in the boundary layer. Accounting for this absorption can cause a reduction in the predicted radiative heat flux impinging on the spacecraft, leading to more efficient designs for heat shields and predictive modeling of hypersonic re-entry flights.