As the inauguration nears, the Capitol has become a fortress. The fences surrounding it, writes NPR's Michel Martin, "are the hallmarks of a country at war, and most tragically, at war with itself."

The test was for NASA's Space Launch System, a successor to the retired Space Shuttle program. It takes eight minutes to generate the power needed to get to space, and ultimately to the moon.

In separate incidents over the weekend, police arrested a 63-year-old woman who claimed to be an officer and a 22-year-old man carrying a firearm, high-capacity magazines and unregistered ammunition.

Russian authorities detained the country's top opposition leader after he landed in Moscow on a flight from Berlin. Navalny had been gone nearly five months since he was poisoned last August.