Engineering topics

Pellicori, Samuel

Publications and source records attributed to Pellicori, Samuel.

3 records

NASA NTRS2017

Segmented Aperture Interferometric Nulling Testbed (SAINT) II: Component Systems Update

"This work presents updates to the coronagraph and telescope components of the Segmented Aperture Interfer-ometric Nulling Testbed (SAINT). The project pairs an actively-controlled macro-scale segmented mirror withthe Visible Nulling Coronagraph (VNC) towards demonstrating capabilities for the future space observatoriesneeded to directly detect and characterize a significant sample of Earth-sized worlds around nearby stars inthe quest for identifying those which may be habitable and possibly harbor life. Efforts to improve the VNCwavefront control optics and mechanisms towards repeating narrowband results are described. A narrative isprovided for the design of new optical components aimed at enabling broadband performance. Initial work withthe hardware and software interface for controlling the segmented telescope mirror is also presented."

high-contrast imaging↗

NASA NTRS2004

Polarization Modeling of the MODIS Instrument

Sunlight reflected from the earth is, to a certain extent, polarized. Radiometers, such as the MODIS instrument on board the TERRA and AQUA spacecraft, are to a certain extent polarizers. Accurate radiometric measurements must take into account both the polarization state of the scene and the polarization sensitivity of the measuring instrument. The measured polarization characteristics of the MODIS instruments are contained in various radiometric models. Continued use of these radiometric math models, over a number of years, have shown where these models can be improved. The current MODIS polarization modeling effort is discussed in the context and limitations of past modeling efforts.

Waluschka, Eugene↗

NASA NTRS2004

Polarization Ray Trace Model of the MODIS Instrument

Sunlight reflected from the earth is, to a certain extent, polarized. Radiometers, such as the MODIS instrument on board the TERRA and AQUA spacecraft, are to a certain extent polarizers. Accurate radiometric measurements must take into account both the polarization state of the scene and the polarization sensitivity of the measuring instrument. The measured polarization characteristics of the MODIS instruments are contained in various radiometric models. Continued use of these radiometric math models, over a number of years, have shown where these models can be improved. Currently a MODIS polarization ray trace model has been created which models the thin film structure on the optical elements. This approach is described and modeled and measured instrument polarization sensitivity results presented.

Waluschka, Eugene↗