<http://schema.org/thumbnailUrl>
<https://drscdn.500px.org/photo/6935913/w%3D160_h%3D160_s%3D1/bb055d82c03ff83756d0872570b1d2cb>
<https://marketplace.500px.com/photos/6935913/aurora-in-the-trees-by-timothy-boocock>