[Show abstract][Hide abstract] ABSTRACT: The New Horizons spacecraft was launched on 19 January 2006. The spacecraft was designed to provide a platform for seven instruments that will collect and return data from Pluto in 2015. The design drew on heritage from previous missions developed at The Johns Hopkins University Applied Physics Laboratory (APL) and other missions such as Ulysses. The trajectory design imposed constraints on mass and structural strength to meet the high launch acceleration needed to reach the Pluto system prior to the year 2020. The spacecraft subsystems were designed to meet tight mass and power allocations, yet provide the necessary control and data handling finesse to support data collection and return when the one-way light time during the Pluto flyby is 4.5 hours. Missions to the outer solar system require a radioisotope thermoelectric generator (RTG) to supply electrical power, and a single RTG is used by New Horizons. To accommodate this constraint, the spacecraft electronics were designed to operate on less than 200 W. The spacecraft system architecture provides sufficient redundancy to provide a probability of mission success of greater than 0.85, even with a mission duration of over 10 years. The spacecraft is now on its way to Pluto, with an arrival date of 14 July 2015. Initial inflight tests have verified that the spacecraft will meet the design requirements. Comment: 33 pages, 13 figures, 4 tables; To appear in a special volume of Space Science Reviews on the New Horizons mission
Space Science Reviews 09/2007; 140(1-4). · 5.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This paper describes a process of spacecraft flight software development that reuses requirements, designs, and implementations. Beginning in 1997, The Johns Hopkins University Applied Physics Laboratory (JHU/APL) developed the flight software for five different space missions: (1) Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED), (2) COmet Nucleus TOUR (CONTOUR), (3) MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER), (4) Solar TErrestrial RElations Observatory (STEREO), and (5) New Horizons, a mission to Pluto and beyond. JHU/APL met strict constraints of budget and schedule by reusing products from each mission for the following one in a successively more comprehensive fashion. Keys to the success of this reuse are consistent external interface protocols, rigorous requirements management, retention of the original development documentation, use of a consistent development process, and a group organization that fosters reuse. The reused packages include bootstrap, task scheduling, uplink, command handling, autonomy, and 1553 bus support.