Aeneas and the Ghost of Creusa. To find out more about Aeneas and his flight from Troy, see this Wikipedia article: link; for information about the image: image source.
Today's image is a dramatic scene from the downfall of Troy; you can see the city burning in the background. The Trojan hero Aeneas has come back to his home in order to rescue his family - his father Anchises, his son Ascanius, and his wife Creusa. Sadly, though, Creusa will not survive their flight; Aeneas will lose her in the chaos and confusion and then be visited by her ghost, as you can see in the shimmering blue image below. You can read all about that in Vergil's Aeneid, Book 2.
You can also find more myths and legends for the week of June 17-23 here. For more information and links to the actual javascript code, see the Myths & Legends Widget Reference Page.