Near Ultraviolet Emission Spectroscopy of the Hayabusa Re-entry

Quantitative time-resolved irradiance measurements are presented of the Hayabusa Sample Return Capsule's entry on June 13, 2010, as measured from 12.6 km altitude with the Australian Ultraviolet Spectrograph (AUS) instrument on board NASA's DC-8 Airborne Laboratory, which was stationed just outside of the landing site at the Woomera Test Range in Australia. The measurements were calibrated against NIST traceable standard calibration lamps on the tarmac at NASA Dryden Aircraft Operations Facility and at NASA Ames Research Center. The recorded spectra cover the wavelength range from 300 to 470 nm over the duration from 13:52:02.5 until 13:52:33.5 UTC. The spectra show shock emission from N 2 +, as well as several ablation products from the heat shield material (CN, Ca, and Al). In addition, the high-temperature tail of gray-body emission is observed to enter the wavelength range after 13:52:13 UTC. This data is evaluated in terms of the temporal evolution of the capsule's stagnation temperature and emissions within the CN and N 2 + manifolds.