NASA's sun-shielded Messenger spacecraft sent back images showing Mercury's single rocky plate is contracting, with massive slabs of rock sliding over one another and creating cliffs that can reach two miles high.
Patty Murray Should Be the Next Senate Minority Leader The Washington senator is a better choice than Elizabeth Warren or Chuck Schumer.
Inside Higher Ed
Fighting Words? A professor compared Hamas to a rabid pit bull. Free speech couldn’t protect him from student vitriol.
What Happened at Slate This Week? Alison Griswold describes her experience reporting on the Germanwings tragedy.
Even Lufthansa’s Exhaustive Psychiatric Tests Couldn’t Have Stopped a Tragedy Like the Germanwings Crash