The internet erupted in controversy over Felisa Wolfe-Simon and colleagues’ claim of a microbe thriving on arsenic. Nearly 15 years later, she’s pursuing new research on the boundaries of life.

To be confirmed as health secretary, Robert F. Kennedy Jr. can afford to lose no more than three Republican votes if all Democrats are united in their opposition to him.

Senators Lisa Murkowski, Susan Collins and Mitch McConnell voted against confirming Donald Trump’s pick for defense secretary. To Capitol insiders, their decisions weren’t surprising.

The president wants to honor a predecessor, William McKinley, by returning his name to North America’s highest peak. The state’s senators prefer the Native name.