The "Pi in the Sky" math challenge gives students a chance to take part in recent discoveries and upcoming celestial events, all while using math and pi just like NASA scientists and engineers. In this problem from the 11th set, students use pi to figure out how much data the NISAR spacecraft collects every day. Materials Pi in the Sky 11: Orbit Observation worksheet – download PDF (for best results, download and print from Adobe Reader) Pi in the Sky 11: Orbit Observation answer key – download