Sending humans to Mars is easy, except for the parts about getting there, landing safely, and surviving on the surface. That’ll take lots of science.

15 ways my husband and I guard our marriage while still loving our friends of the opposite sex. With recent allegations of indiscretion against a prominent megachurch pastor, some Christian leaders have doubled down on the so-called Billy Graham Rule, which dictates that men and women should never meet alone. Southeastern Baptist Theological Seminary president Danny Akin tweeted, “A valuable lesson we all can learn from this tragic situation: follow the @BillyGraham rule. If you are married, never be alone with someone of the opposite sex who is not your spouse. Never!” This rule, in its most pristine form, renders…

15 ways my husband and I guard our marriage while still loving our friends of the opposite sex. With recent allegations of indiscretion against a prominent megachurch pastor, some Christian leaders have doubled down on the so-called Billy Graham Rule, which dictates that men and women should never meet alone. Southeastern Baptist Theological Seminary president Danny Akin tweeted, “A valuable lesson we all can learn from this tragic situation: follow the @BillyGraham rule. If you are married, never be alone with someone of the opposite sex who is not your spouse. Never!” This rule, in its most pristine form, renders…