Image description: two photos of a singular replica of a triangular shaped satellite, one from directly below showing its thruster and one from the front. In the latter picture, the US flag is visible above a star made up of red, white, and blue stripes. Around the star in black print is the words: "American Revolution Bicentennial 1776-1976".
The Viking program was a pair of indentical NASA space probes creatively named Viking 1 and Viking 2. The probes each consisted of an orbiter and lander. They were both launched in the same year (1975), and landed on Mars in 1976.
As part of the celebrations of 1976 being 200 years since the start of the American Revolution and the Viking missions being a wholly US mission, the orbiter bore a design honoring that fact.
This is a replica as the orbiters remained at Mars, though they are not necessarily still in orbit around the red planet.