This is very welcome, as I've often found the official NASA/USGS tools to be difficult to use in practice. One thing that I don't understand is why coverage ap

This is very welcome, as I've often found the official NASA/USGS tools to be difficult to use in practice. One thing that I don't understand is why coverage appears to be poor or non-existant at high latitudes (say, above 70 degrees). Shouldn't there be a lot of images here because of the near-polar orbit (i.e. high latitudes should be sampled frequently)? Also, a graticule would be handy, as it can be tricky to find a specific place with the simple basemap. But thanks very much for this tool!