Intensified Low-Resolution Optical Spectroscopy of the Stardust Sample Return Capsule Entry

摘要

The radiation emitted by the Stardust sample return capsule during reentry into Earth’s atmosphere onn15 January 2006 wasmeasured with a staring airborne intensified camera, equipped with an objective transmissionngrating. The instrumental setup was designed to provide low-resolution spectra of the capsule’s radiation, even ifnother instruments would fail in tracking the object. Spectra were recorded at the video frame rate of 30 Hz. Thenspectra covered the range of 380–860 nm, with a dispersion of 2:3 nm=pixel and a full-width-at-half-maximumnresolution of 7 nm. Fully calibrated results, to an absolute precision ofu000117%, are presented for the time period fromn09:57:17 to 09:57:43CoordinatedUniversal Time, averaged over periods of 1 s. The data provided records of theCNnband intensity detected throughout flight (unsaturated), the continuumemission (partially saturated), and the shocknplasma emissions of oxygen and nitrogen during peak heating (partially saturated). A spectrumof wake radiation isnalso presented.