Cosmic Ray Rejection and Image Processing aboard the Next Generation Space Telescope
- Stockman, H.S
- Proc. Of the 34 IAC,
NGST ISIM will certainly contain an IR wide-field camera and a spectrograph as well as one or more instruments working at MIR and/or visible wavelengths. Owing to their very nature, and to the scientific requirements they are supposed to meet, all instruments rely on a significant number of intermediate read-outs in order to achieve very low read-noise. Back of the envelope calculations show that, even under the most optimistic downlink scenarios it will be "impossible" to send all the intermediate readouts to the ground station(s), thus calling for substantial on-board data processing and compression. Assuming a comprehensive model payload operated following the most demanding read-out strategy, we have analyzed possible ways to co-add intermediate read-outs and compress the resulting images in order to significantly reduce the data rate to be transmitted to the ground, while maintaining the science output of the NGST instrument. The final aim of this study is to define the On-board Data Management architecture and assess its feasibility with respect to the NGST schedule. The presentation of the work is available at http://astro.estec.esa.nl/NGST/.