In this March, 2015 photo, a person sits at an upright piano that had been hauled up to Topanga Lookout in the Santa Monica Mountains in Calabasas, Calif. For a couple of days last week, a Southern California hilltop was alive with the sound of mystery. Hikers venturing to Topanga Lookout found a battered upright piano sitting on a graffiti-scrawled concrete slab with a panoramic view over the mountains between Calabasas and the Pacific Ocean. Turns out, the piano was used for a music video by Seattle-based artist Rachel Wong. The cinematographer, Michael Flotron, says he and four others used a dolly and rope to haul the 350-pound instrument a mile up the trail on Tuesday. After the shoot, it was too dark to get the piano back down. Flotron says people seem happy to leave it there. But if necessary, he'll haul the piano back down. (Photo by Michael Flotron/AP Photo)

Sophie and Sarah, old English sheepdogs, watch the sea from their plastic chairs. Amateur photographer Cees Bol, from the Netherlands, documents the lives of his beloved pooches Sophie and Sarah by taking pictures of them every day. (Photo by Cees Bol/Caters News Agency/Mercury Press)

Revellers take part in a zombie parade to celebrate Halloween in Kiev, Ukraine, October 31, 2015. (Photo by Valentyn Ogirenko/Reuters)

Actors portraying "corrupted people" participate in the "Unmask the Corrupt" event, organized by the Transparency International non-governmental organization to create awareness on corruption, in Lima, November 12, 2015. (Photo by Mariana Bazo/Reuters)

New Jersey based artist, Joe Iurato creates art using hand-cut paper and spray paint to make small wood cutout figures and placed in public spaces. According to Iurato, “a puddle can become a lake, a small crack in a cement wall can become a magnificent climb, a planter box can become a place for a child to play, and a shadow might be a tangible space for a few seconds a day”. Photo: “Small World”. (Photo by Joe Lurato)

Illuminated Cut Paper Light Boxes by Hari & DeeptiDeepti Nair and Harikrishnan Panicker (known collectively as Hari & Deepti) are an artist couple who create paper cut light boxes. Each diorama is made from layers of cut watercolor paper placed inside a shadow box and is lit from behind with flexible LED light strips. The small visual narratives depicted in each work often play off aspects of light including stars, flames, fireflies, and planets.

Iranian artist and designer Mehdi Ghadyanloo, with the help of the municipality, is slowly brightening up the city of Tehran one wall at a time. The 33-year old street artist has been painting murals and walls in Tehran for the last 5 years age, during which he’s reported to have painted over one hundred walls.

The Chicago Air & Water Show is an annual air show held on the shore of Lake Michigan in Chicago, Illinois. The show has been held each year since 1959 and is Chicago's second most popular festival. In 2005, 2,200,000 watched the Chicago Air and Water Show.