A holiday edition of Planetary Radio welcomes the Planetary Society’s Senior Editor back from the annual meeting of the American Geophysical Union. Emily reports on amazing developments in planetary science she discovered at the huge conference. Someone will win a half-scale model of the LightSail 2 cubesat when Bruce Betts joins Mat Kaplan for this week’s What’s Up. Related links are here: http://www.planetary.org/multimedia/planetary-radio/show/2017/1220-emily-lakdawalla-agu-report.html