Description of the payload
Is a modified version of the LPMA instrument (Limb Profile Monitor of the Atmosphere originally created to made Earth's limb measurements) used to observe the Earth's atmospheric emission at nadir, to determine the vertical profiles of various atmospheric gases such as H2O, CO2, CO, O3, N2O, & CH4 from high resolution atmospheric spectra. Their major goal is the preparation of the so called IASI mission, which is a satellite instrument dedicated primarily to operational meteorology, hence it is also known as IASI-balloon.
The instrument is composed by a BOMEM DA2 infrared Fourier transform spectrometer coupled with a movable mirror. An optical head with an aquisition mirror looks down and made the nadir observation while two references blackbodies one warm and the other cool are used for reference purposes. A CCD camera is used to image in the visible the atmosphere observed by the spectrometer and to make corrections in the instrument attitude commanding the aquisition mirror. The instrument is installed in the same gondola developed by the CNRS for the LPMA instrument, wich have an azimuth control system to compensate the balloon motion. An onboard PC computer controls the instruments during the flights, recording the interferograms and ensuring the telecommand and telemtry link with the ground station.
Details of the balloon flight and scientific outcome
Launch site: European Space Range, Kiruna, Sweden
Balloon launched by: Centre National d'Etudes Spatiales (CNES)
Balloon manufacturer/size/composition: Zero Pressure Balloon
The balloon was launched at 18:05 utc on August 5, 2002 using the auxiliary balloon method.
After and ascent phase of near two hours, the balloon reached float altitude at 31 km at 19:55 utc and started an west path with a controlled descent to 26 km as can be seen in the map at left (click to enlarge). At 22:17 utc the separation command was transmited and the payload landed 200 km southwest of Kiruna. During the float phase, due to the flight was done during the boreal summer the balloon shinning under the midnight sun was clearly visible from Oulu, a Finnish city located 300 km from Kiruna. The picture at right was obtained by the amateur astronomer Tomi Leppikangas.
External references and bibliographical sources