Let’s look at some cover images shall we?

Two by Jack Gaughan. And yes, that’s the same John Jakes now known for North and South.One by Sergio Leone for this James Bond/SF adventure mashup.I believe Robert McGinnis did this Carter Brown cover. Less skin than usual for that series, but the trippy wallpaper makes it, like the Leone, very much of its time.#SFWApro. All rights to images remain with current holder.