made systematic size measurements of hematite spherules embedded in the walls of Victoria Carter at different heights. (Victoria Crater is a large and deep crater.) These measurements showed a clear variation of spherule size with elevation within the sediments of Meridiani Planum. The smaller spherules were higher up, the larger ones lower down. The lowest spherules near the bottom of Victoria Crater had similar diameters to the spherules in Eagle Crater, and the elevations of these distant locations were nearly equal. No papers were written on spherule size that covered areas of the rover's traverse south from Victoria Crater to the enormous Endeavour Crater. However, searches of the archive of the images taken by the rover's Microscopic Imager show some of the largest blueberries photographed are close to the rim of Endeavour Crater (see Figure 11). Numbers of Blueberries & Loose Spherule Surface Density There are no peer-reviewed published estimates of the number of loose hematite spherules on Meridiani's soils or embedded hematite spherules in the plain's sediments. However, the reader can sense how mind-boggling big those numbers are with a photograph of an area of soil with a typical surface density of the hematite spheres. Such a photograph has been published. Figures 12 and 13 are true-color and false-color versions of the photo. The spherules are easier to see in the published false-color version (Figure 23). Click on it to enlarge it. The sampling target of Figures 12 & 13 had 29% coarse hematite coverage. The range of coverage among similar targets was 10% to 40%. These targets were sampled over a wide area, between Sol 70 (2004-04-04) and Sol 999 (2007-11-15). The parts of the plain Opportunity studied are not special: Compared to the rest of Meridiani Planum, they do not have high surface hematite levels. To see this, look at the plain's surface hematite map (Figure 1b) and the small blue line (labeled OT ) indicating the route of Opportunity's Traverse of the plain. The mind-bogglingness of the number of loose hematite spherules hits when Figures 12 & 13 are extrapolated to the plain's whole surface area (about 150,000 km2): 150,000 km2 is close to 2/3's the area of the main island of Japan (Honshu) and also 72% the area of the main island of the UK (Great Britain), it is also bigger than the land areas of 30 of the 50 states of the USA. The