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Letters to the editor Howard Mark’s comments on the Periodic Graphics article about space elevators were very much to the point (C&EN, Aug. 5, 2024, page 5). I would like to add one other comment. The space elevator design discussed in the article is the type often discussed in the scientific (and science fiction) literature. It consists of a space station well above the height of geostationary orbit, anchored by an extremely strong cable to a point on Earth. Freight and passengers are conveyed up or down the cable. As Mark points out, the anchor point has to be on the equator. Because the station is at a height at which its orbital velocity would be much lower than that of a geostationary satellite, it is dragged along by the cable. Thus the cable is under a good deal of tension. As Mark points out, the anchor point has to