Accelerate progress in our three core enterprises — Explore Worlds, Find Life, and Defend Earth. You can support the entire fund, or designate a core enterprise of your choice.
Orbit determination of Siding Spring This diagram is indicative of how the orbit determination accuracy for comet C/2013 A1 (Siding Spring) evolved over time. It shows a derived quantity: the expected encounter distance from Mars. NASA / JPL-Caltech