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1	Performance of the BRITE Prototype Photometer Under Real Sky Conditions Bode, Willem January 2011 (has links) Wide-field photometry is prone to various degradations, such as atmospheric ex- tinction, varying point spread functions, and aliasing in addition to classical noise sources such as photon, sky background, readout, and thermal noise. While space- borne observations do not suer from atmospheric eects, varying star images over a large sensor and aliasing may seriously impede good results. A measure of the achievable precision of ground-based dierential photometry with the prototype photometer for the BRITE satellite mission is reported, using real sky observa- tions. The data were obtained with the photometer attached to a paramount tracking platform, using the Image Reduction and Analysis Facility Software (IRAF) image reduction and analysis methods as well as the author's own Matlab Code. Special emphasis is placed on the analysis of varying apertures for vary- ing point spread functions, which shows that the accuracy can be improved by taking into account the statistics for each star instead of using a xed aperture. In addition a function is dened, which describes the expected error in terms of instrumental magnitudes, taking into account Poisson distributed noise and mag- nitude independent noise, mainly aliasing. This function is then t to observed data in a two-dimensional least squares sense, providing a calculated aliasing error of 7 millimagnitudes. This function is furthermore rewritten in terms of the stan- dard magnitude B. A maximum magnitude can then be determined for a certain precision, which shows that the Bright Target Explorer (BRITE) can reach a pho- tometric error of 1 millimagnitude for stars with magnitude B < 3:5, assuming the worst case duty cycle of 15 minutes. / <p>Validerat; 20110211 (anonymous)</p> photometry BRITE UTIAS millimagnitude wide field of view large FOV image correction noise sources
2	Propulsion System Development for the CanX-4 and CanX-5 Dual Nanosatellite Formation Flying Mission Risi, Benjamin 04 July 2014 (has links) The Canadian Nanosatellite Advanced Propulsion System is a liquefied cold-gas thruster system that provides propulsive capabilities to CanX-4/-5, the Canadian Advanced Nanospace eXperiment 4 and 5. With a launch date of early 2014, CanX-4/-5's primary mission objective is to demonstrate precise autonomous formation flight of nanosatellites in low Earth orbit. The high-level CanX-4/-5 mission and system architecture is described. The final design and assembly of the propulsion system is presented along with the lessons learned. A high-level test plan provides a roadmap of the testing required to qualify the propulsion system for flight. The setup and execution of these tests, as well as the analyses of the results found therein, are discussed in detail. aerospace microsatellite nanosatellite propulsion formation flying canx4 canx5 canx-4 canx-5 canx-4/-5 SFL UTIAS cold-gas thruster satellite CNAPS NANOPS nano sulfur hexafluoride SF6 vibration testing spacecraft environmental testing propulsion testing low earth orbit canx2 canx-2 station keeping orbit maneuver orbital station-keeping liquefied cold-gas propulsion micropropulsion engineering space canadian space flight laboratory canadian advanced nanospace experiment PSLV micro-propulsion thruster interferometry ground moving target indicator on-orbit servicing and inspection 0538

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Performance of the BRITE Prototype Photometer Under Real Sky Conditions

Propulsion System Development for the CanX-4 and CanX-5 Dual Nanosatellite Formation Flying Mission