Porkchop Plot
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Porkchop plot Porkchop plot (also pork-chop plot) is a chart that depicts orbital trajectories for spacecraft. It is named for the characteristically porkchop-shaped contours that display combinations of launch date and arrival date characteristics of an interplanetary flight path for a given launch opportunity to Mars or any other planet.cite web author=Goldman, Elliot url=http://ccar.colorado.edu/asen5050/projects/projects_2003/goldman/ title=Launch Window Optimization: The 2005 Mars Reconnaissance Orbiter (MRO) Mission" publisher=. Representative porkchop plot for the 2005 Mars launch opportunity. What a porkchop plot really represents, says Johnston, is a solution to some orbital mechanics equations known as Lambert's theorem, which he sums up thusly: "If I know where the Earth is and where Mars is on some given day, and I know how long I would like to take to get to Mars, then I can compute the departure conditions I. Porkchop plot (also pork-chop plot) is a chart that shows contours of equal characteristic energy (C3) against combinations of launch date and arrival date for a particular interplanetary flight.[1]. By examining the results of the porkchop plot, engineers can determine when launch opportunities exist (a launch window) that is compatible with the capabilities of a particular spacecraft.[2] A given contour, called a porkchop curve, represents constant C3, and the center of the porkchop the optimal minimum C3. A porkchop plot is a data visualization tool used in interplanetary mission design which displays contours of various quantities as a function of departure and arrival date. Example pork chop plots for 2016 Earth-Mars transfers are shown here. The x-axis is the Earth departure date, and the y-axis is the Mars arrival date. The contours show the Earth departure C3, the Mars arrival C3, and the sum of the two. C3 is the âœcharacteristic energyâ of the departure or arrival, and is equal to the \(v_{\infty}^2\) of the hyperbolic trajectory. A porkchop plot (also pork-chop plot) is a chart that shows contours of equal characteristic energy (C3) against combinations of launch date and arrival date for a particular interplanetary flight. By examining the results of the porkchop plot, engineers can determine when launch opportunities exist (a launch window) that is compatible with the capabilities of a particular spacecraft. A given contour, called a porkchop curve, represents constant C3, and the center of the porkchop the optimal minimum Representative porkchop plot for the 2005 Mars launch opportunity (horizontal axis: departure dates, vertical axis: arrival dates) A given blue contour represents a solution with a constant C3. The center of the porkchop is the optimal solution for the lowest C3. The red lines represent trips with the same travel time for the trajectory. A porkchop plot (also pork-chop plot) is a chart that shows contours of equal characteristic energy (C3) against combinations of launch date and arrival date for a particular interplanetary flight.[1]. Porkchop plots are an easy, quick, reliable means for planning interplanetary (or inter-lunar) travel. They display, in 3 dimensions of data, the time to a node on the X-axis, the duration of transfer on the Y-axis, and the color of the plot indicates the relative amount of dV needed for that node to make an encounter from your orbit to the target planet. Red requires more fuel than blue, and time increases from the lower left to the upper right..