Lunar Geology


The Appllo project provided enormous amout of information about lunar geology. But, the Clementine mission let us know that the several riddles still remain on the lunar geology. We carried out the semi quantitative study about lunar geology using mult-bands spectrometry imaging system, and aim to be the first amateur to succeed in the lunar spectrometry.


The multi-bands spectrometry is based on the method of Saiki et al.(2000) and Lucey et al. (1998).
In the lunar basalt, TiO2 is contained as mainly ilmenite (FeTiO3). About the low or middle Ti content type basalt, the refractance data of different bands on lunar surface are determined by ilmenite contents (Lucey et al. 1998). But, space weathering make some influence to the multi-band refractance. Such a maturity index is compensated by the treating Lucey's method (Lucey et al.,1998).
Saiki et al.(2000) made some PC softwares based on the Lucey's method. It is able to download from Dr. Saeki's homepage.


Telescope: FS-152 (15cm F8, Takahashi Optics, Japan)
Equitorial: GX-1 (Full automatic, ERDE Optics, Japan)
Cooled CCD camera: ST-9E (512~512 pixel, SBIC Co.Ltd, USA)
Filter wheel: CFW-8A (SBIC, USA)
Band pass filter: BP-42 (420nm) and BP-75(750nm),(Kenko, Japan)

These band-pass filters are ordinary for industrial use, and were ordered for the CFW-8A filter cell size. It costs 150 $ for each filter. The optical charactristics are shown below. These band-pass filter is able to order to the Eagle Trading Company, Kanagawa Pref. Japan.

In this condition, the a pixel size is assumed to about 6 km square, so that full moon is just size as whole tip. The pixel size is same as whole moon TiO2 mapping (e.g. Lucey et al. 1998)

Flat field correction is important for image processing. We made a optical integrating ball to take flat field images according to Saiki et al.(2001). Imaging condition is same as the filtered lunar images.

The obtained flat field image has good perfomance. The conbination correction of dark and flat is carried out using "Stella-image 3 (Astroarts Inc.)".

Studtents at work


The filtered lunar image were obtained on April 24th, 2002. The phase of lunar was 11.3. The diameter of telescope was down-sizing to 5cm. The cooled temperature of CCD was -20 C. The exposure time was 0.11 sec.

To correct lunar phase using image processing, the filter image is generated by the program "Lunar Filter" (lf.exe: Saiki et al.,2000). And to decide the colimation factor of filter image, some crater positions and mesh map image are generated by the program "Lunar Map" (lm.exe: Saiki et al., 2000).

Obtained two images are composite to Ti map using tife.exe (Saiki et al.,2000)


TiO2 contents map is colored using "Scion-image" (Scion Inc.). The light colored area is corresponded to the high TiO2 contents area, while the dark colored area is low TiO2 contents area. It conflicted with the Clementine image (e.g. Lucey et al, 1998) and Saiki et al.(2000).

Further practice

More detailed image will be get another telescope system. The test image of the Male Selenites is usage of ;
Celestron C5 (12.5cm in diameter, F5)
ST-5 (old instrument of SBIC cooled CCD system)
The pixel size reached to about 2 km square.


Near side of Saiki's Labo
Paul G. Lucey Presonal Website
Clementine -DSPSE-

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