Looking at some of the photos returned by NASA’s Solar Dynamics Observatory (SDO), you’d think contemporary solar observing had little in common with what was being done at Kodaikanal c. 1900-1910. But in addition to the dramatic images of solar loops like the one shown above, SDO also sends back sunspot records that closely resemble the photos and charts produced by … Continue reading Wallpaper Wednesday: SDO and Sunspots