SPECTRORADIOMETER CALIBRATION WITH UAV-BORNE LED

We investigated the feasibility and the limitations of using a UAV-borne (Unmanned Aerial Vehicle, or drone) light source for calibrating a starphotometer (essentially a telescope mounted spectroradiometer). This is a proof-of-concept experiment for future use of satellite- and balloon-borne calibration light sources. We measured a narrow-band, three-colour LED source at three fixed UAV positions between 700 and 1500 m distance and at 115 m elevation over a 5–10° elevation angle range above the horizon (equivalent to a 0,09–0,20 airmass range). While the calibration was deemed to show good potential, it was limited by the use of a narrow-band light source. Line-of-sight extinction profiling is a very interesting product that can be extracted from these types of measurements.