This is the STS-115 insignia.

This is the STS-115 insignia. This mission continues the assembly of the International Space Station with the installation of the truss segments P3 and P4. Following the installation of the segments utilizing both the shuttle and the station robotic arms, a series of four space walks will complete the final connections and prepare for the deployment of the station's second set of solar arrays. To reflect the primary mission of the flight, the patch depicts a solar panel as the main element. As the Space Shuttle Atlantis launches towards the ISS, its trail depicts the symbol of the Astronaut Office. The starburst, representing the power of the sun, rises over the Earth and shines on the solar panel. The shuttle flight number 115 is shown at the bottom of the patch, along with the ISS assembly designation 12A (the 12th American assembly mission). The blue Earth in the background reminds us of the importance of space exploration and research to all of Earth's inhabitants. The NASA insignia design for shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced.