Solar Dynamic Observatory

Soufli, S.L. Baker, D.L. Windt, E.M. Gullikson, J.C. Robinson, W.A. Podgorski, and L. Golub, Atomic force microscopy characterization of Zerodur mirror substrates for the extreme ultraviolet telescopes aboard NASA s Solar Dynamics Observatory, Appl. Opt. 46(16), 3156 3163 (2007). 

Launched in 2010, the Solar Dynamic Observatory (SDO) was an Explorer-class mission which achieved geosynchronous orbit in order to observe the Sim (Mason and Starin, 2011). SDO required a large amount of propellant, close to half of the overall mass of the vehicle (Willis, 2012). The PMD used on this satellite was a sponge because maintaining a propellant center of mass and reducing liquid slosh were the two main objectives for PMD design. 

Mason, E, Starin, S.R., 2011. The effects of propellant slosh dynamics on the solar dynamics observatory. In AIAA-2011-6731, Guidance, Navigation, and Control Conference, Portland, OR, August 8-11. 

The Astronomical Ephemeris (formerly The American Ephemeris and Nautical Almanac), published annually by the U.S. Naval Observatory and the U.K. Alamanac Office contains the most current available data on orbital dynamics of solar system bodies. 

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