On this week’s If Then, Slate’s April Glaser and Will Oremus discuss Elon Musk’s plan to… colonize Mars? They explain how sanctuary cities may unwittingly be sharing data with ICE through police surveillance tech. And Facebook VP Adam Mosseri, head of the news feed, joins the show for a wide-ranging interview. He explains how his team thinks about its responsibility to inform the public, and how they tackle complex problems ranging from fake news in the United States to Facebook-fueled hate campaigns in Myanmar.

Podcast production by Max Jacobs.

If Then plugs:

You can get updates about what’s coming up next by following us on Twitter @ifthenpod. You can follow Will @WillOremus and April @Aprilaser. If you have a question or comment, you can email us at ifthen@slate.com.

If Then is presented by Slate and Future Tense, a collaboration among Arizona State University, New America, and Slate. Future Tense explores the ways emerging technologies affect society, policy, and culture. To read more, follow us on Twitter and sign up for our weekly newsletter.

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