Even with improvements to the UI to increase intuitive usage a help/orientation dialog would assist users who have very little experience with the concepts and technologies in play on the site. This could be a modal with static text / images and should at the very least cover the following topics:
What solar eclipses are and about how often they happen
What Cesium is and how to read and interact with the Cesium widget
What the "Now Showing" and "Other Eclipses" sections depict and how to interact with them
Even with improvements to the UI to increase intuitive usage a help/orientation dialog would assist users who have very little experience with the concepts and technologies in play on the site. This could be a modal with static text / images and should at the very least cover the following topics: