skim the top of Pluto’s atmosphere where it would cut down on some of
the dust through atmospheric drag. And the other was to turn New Horizons itself so that the antenna would shield the rest of the spacecraft.
Another thing we did was to practise running the whole encounter
through, having somebody invent data from the satellite. We ran the
simulation three times, as it would be by the clock, with data coming
down, people detecting moons, calculating orbits, calculating how
much stuff there would be and how risky that might be. We simulated
making recommendations, with NASA officials there to run through the
procedure. In the end, all of that was very useful because it turned
out that to get anything risky we had to have a thousand satellites hiding in between Pluto and Charon to even make us consider trajectory
changes. And it helped us make sure we got the best data in the end.
Everybody was very happy with the final decision. Everybody was holding their breath a bit on encounter day, but it all went perfectly.’
Figure 5: Discovery image of Pluto’s tiny moon Styx in 2012, overlaid with orbits of the satellite system, which gave
cause for concern to the Pluto Encounter Planning (PEP) Team. Credit: NASA/ESA/L. Frattare (STScI)
Complex and dynamic world
So what have the New Horizons’ team learned so far from the encounter? It is beyond the scope of this article to describe all the discoveries made by the spacecraft, so we focus here on some of the most
significant ones. (A list of recommended further reading is suggested at
the end)
Planetary mission scientists have learned to expect the unexpected,
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