topic lunar projection from earth based projection system in Data Management Questions

lunar projection from earth based projection system

thangjamsingh — Thu, 14 Oct 2010 06:15:10 GMT

Hi,
Anyone please, can tell regarding the map projection. I have images of Moon, which is originally generated through Geographic lat/long, WGS 84 datum. I am working with ArcGIS 9.2. I worked applying the conversion factor of Moon ie 30.333 km is equal to 1 degree, in case of my applications. I try to reproject the image in Moon spheroid, it is done, I apply the flattening factor of the major and minor axis, I was very happy that I did it, when I check the projection it is showing moon spheroid, but in my application work the scale is not coming with respect to the Moon. And when I check the datum, it is showing unknown. So please tell me, is it not possible to project the images who were originally processed in Geographic Lat/long, WGS 84 datum to lunar projection (datum).
I ll be very thankful to you.
with regards,
guneshwar
gune.ishwar@gmail.com

Re: lunar projection from earth based projection system

MelitaKennedy — Thu, 14 Oct 2010 18:40:53 GMT

Hi,
Anyone please, can tell regarding the map projection. I have images of Moon, which is originally generated through Geographic lat/long, WGS 84 datum. I am working with ArcGIS 9.2. I worked applying the conversion factor of Moon ie 30.333 km is equal to 1 degree, in case of my applications. I try to reproject the image in Moon spheroid, it is done, I apply the flattening factor of the major and minor axis, I was very happy that I did it, when I check the projection it is showing moon spheroid, but in my application work the scale is not coming with respect to the Moon. And when I check the datum, it is showing unknown. So please tell me, is it not possible to project the images who were originally processed in Geographic Lat/long, WGS 84 datum to lunar projection (datum).
I ll be very thankful to you.
with regards,
guneshwar
gune.ishwar@gmail.com

I think you are running into a known issue or two in ArcMap/ArcGIS. Map projections and datum transformations for vector data are handled by the projection engine library (pe.dll). Rasters use both pe.dll and another library. The other library may not be able to save a moon-based coordinate system in that particular raster format. What format is the data? (tiff, jpeg, GRID)

If you're trying to measure features in ArcMap, I believe that it was hard-coding an earth ellipsoid when calculating the measurements.

You may want to check out PIGWAD (http://webgis.wr.usgs.gov/) which has some tools and forums specifically about non-earth data.

Melita

Re: lunar projection from earth based projection system

thangjamsingh — Sun, 19 Dec 2010 04:27:27 GMT

I am using *.img data format. I any measurement I apply this conversion factor. I am very thankul and happy with your reply.