Trouvelot's fascination with the sun inspired many accomplished drawings during his time at the Harvard College Observatory. The telescope at Harvard—known as the Great Refractor, as it measured over 20 feet in length and employed a 15 inch-diameter lens—was then among the finest in the world, allowing the artist-astronomer to examine the surface activity of the sun in unprecedented detail. The sun so inspired Trouvelot that his first published astronomical paper explored the topic of veiled solar spots, the subject of this print.