Polarized microwave emission from dust is an important foreground that may contaminate polarized CMB studies unless carefully accounted for. Modeling of polarization from dust requires a quantitative understanding of grain alignment. I review the current status of grain alignment theory outlining recent advances in quantitative description of the alignment. In particular, I show that the grain-...

Contemporary land-survey micro-satellites have general mass up to 100 kg and are placed on the orbit altitudes from 600 up to 800 km. For such spacecraft some principle problems on attitude determination, in-flight calibration and alignment are considered and elaborated methods are presented for their solving. We present discrete algorithms for calibration and alignment of the low cost strap-do...

We have performed an assessment of the optical alignment of the WFC3 instrument in its final flight configuration, including the UVIS-1’ and IR-4 detectors, during the 3 thermal-vac test in March 2008. Both detectors are found to be aligned to well within tolerance in all degrees of freedom. The corrector settings, after adjustment to optimize image quality, are within the budgeted range for gr...

The accurate co-alignment of the transmitter to the receiver of the BepiColombo Laser Altimeter is a challenging task for which an original alignment concept had to be developed. We present here the design, construction and testing of a large collimator facility built to fulfill the tight alignment requirements. We describe in detail the solution found to attenuate the high energy of the instru...

The flight software for the on-board Apollo Primary Guidance, Navigation and Control System provides attitude and trajectory control, recursive navigation, targetting, inertial subsystem moding and alignment, prelaunch checkout, crew interaction and telemetry processing for each spacecraft. To develop and flightqualify this complex software package, an all-digital, instruction-by-instruction si...

Alignment technology plays an important role in navigation, and is used extensively throughout military civilian applications. However, the existing in-flight alignment methods cannot be applied to low-cost based strap-down inertial navigation system/global positioning system integrated system, short-endurance high-speed rotation flight bodies, since they quickly obtain results meet accuracy re...

In spaceborne dual-antenna (i.e., single-pass mode) interferometric synthetic aperture radar (InSAR) system, the alignment of the master and slave antenna beam is crucial. In order to achieve the best interferometric performance, antenna beams should be coincided with each other between the master and slave. The beam alignment of the first spaceborne dual-antenna InSAR system, the Shuttle Radar...