The planet’s rotation fluctuates as it travels around the sun, and measurements suggest we’re losing more than a millisecond during the long days of summer.The Earth and the moon in conjunction, captured by the Galileo spacecraft in 1996. The moon’s gravitational tug is responsible for tidal changes on Earth, which affect the speed of its spin and the length of its days.

Our series reveals the math hidden in familiar places. How much do you know about taxicab geometry, triangular numbers, the golden ratio and more?

The task force recommends which screenings and other preventive health measures must be covered by insurance.Robert F. Kennedy Jr. also recently fired 17 members of the advisory committee on immunization to the Centers for Disease Control and Prevention, saying that the move would restore the public’s trust in vaccines.

The letters, many of which were already available online, detail why the regulators initially declined to approve some drugs. All eventually passed muster.Dr. Marty Makary, the F.D.A. commissioner.

Doctors and hospitals were subpoenaed for private information on gender-related care for minors, the latest move by the Trump administration to stop the treatments.Attorney General Pam Bondi said Wednesday that “medical professionals and organizations that mutilated children in the service of a warped ideology will be held accountable.”