Creating Mineral Moon Maps for CubeSats Missions

CREATING MINERAL MOON MAPS FOR CUBESAT MISSIONS . B. Cameron1, E. Woest1, M. Raouf1,2, B. Foing1,2, F. Fazel Hesar2,3, P. R. Mitra4, P. Ananwatanyoo4, A. R. pacheco5, U. N. A. N. Sonou5, C. Irakleous3. 1Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands; [email protected], 2ILEWG LUNEX-EuroMoonMars Earth-Space, ESTEC European Space Agency, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands; [email protected], 3Leiden Institute of Advanced Computer Science, P.O. Box 9504, 2300 RA Leiden, The Netherlands; [email protected]enuniv.nl, 4Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, Netherlands; prath[email protected] and Pan[email protected], 5Inholland Delft, Inholland University of Applied Sciences, P.O. Box 3190, Rotterdamseweg 141, 2628 AL; Delft, Netherlands; sonou4[email protected] and alexrino[email protected], Introduction: The main goal of this project is making a mineral moon map using visual data and a relatively simple setup as a preparation for a CubeSat mission. To achieve this goal two main methods of obtaining data are compared. The aim of the project is to compare the methods, testing there feasibility and gain an idea of what to expect from the results of the CubeSat mission. First method focusses on combining a spectrograph with an RGB camera setup. Using an imaging system with filters in Red (R), Green (G), and Blue (B) a lunar map has been produced using many exposures and a lucky imaging technique was used to counteract the turbulent effects of the atmosphere. The imaging was achieved by using a relatively small 200mm aperture 1m focal length Newtonian reflector telescope, with an ZWOptics ASI1600MM actively cooled monochrome camera. The relatively small aperture allows for the lucky imaging technique to be used, as the aperture is around the optimal 3.4r0 for average seeing conditions [1][2]. Deconvolution sharpening was applied to the resulting image. With these images, areas were selected for spectroscopic measurements. There were two types of measurements taken: point scans, in which a single spot got observed over a long time to achieve high signal to noise ratio, and line scans, where the moon drifted by while constantly taken the data resulting in information over larger areas of the moon. These spectra were analysed for the presence of minerals with a main focus on pyroxene, plagioclase and olivine. Using a focus profile scan across a point source (star) with the spectrograph enables the spectroscopic data to be matched in resolution to pixel values on the RGB lunar image. This allows for correlating spectrograph measurements to RGB values. This potentially can allow for present minerals to be matched to the RGB values of the image. Secondly hyperspectrographic data gets taken. This data provides information over the full lunar disk which gets used as a comparison to test the validity of the spectrograph and imaging system setup. Figure 1: Results of the first mineral moon map using RGB imaging. Numbered points show different observed mare, highlands are named based on colors and there is one transitional measurement. Lines indicated positions of line measurements taken. Figure 2: Spectra correlating to locations on image shown in figure 1. Multiple scans of the lunar surface will be performed with a hyperspectrograph attached to a 200mm aperture 2032mm focal length telescope. This hyperspectral data will be processed in order to extract information about the lunar composition, with the help of a machine learning algorithm. Predicted composition based on the RGB and spectrograph correlation can then be compared to hyperspectral data. The results of these approaches will aid in the selection of the instrumentation for the CubeSat proposals for both Lunar observation and a Lunar rover. If RGB data allows for accurate prediction of lunar minearology, this can serve as a lower-cost option in comparison to the hyperspectral camera. Lower cost and uncomplicated systems are preferential for CubeSat missions. Therefore exploring the feasibility of this technique is valuable information for designing a lunar CubeSat mission. References: [1] David L. Fried (1978) J. Opt. Soc. Am. 68:1651-1658 [2] Fried, David L. (1966) J. Opt. Soc. Am. 56 (10): 1372