Interesting read. Free PDF available.

https://www.nap.edu/catalog/13117/vision-and-voyages-for-planetary-science-i... https://www.nap.edu/catalog/13117/vision-and-voyages-for-planetary-science-in-the-decade-2013-2022?utm_source=NASEM+News+and+Publications&utm_campaign=eb1177b447-May_the_4th_Be_With_You_2017&utm_medium=email&utm_term=0_96101de015-eb1177b447-103988541&mc_cid=eb1177b447&mc_eid=82b5b9ba2e

Enjoy!!

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