Joel Achenbach

• Health

The disease is striking young people who have no obvious risk factors.

• Science

The eruption won’t produce the fine ash that shut down air travel across much of Europe in 2010. But it’s not a tourist-friendly event, and the situation remains fluid.

• Science

Scientists speaking at an annual conference described how the bludgeoning of young Earth may have primed the planet to be more congenial to life.

• Science

The scientific community got its first description of the material recovered by NASA’s OSIRIS-REx mission at the fall meeting of the American Geophysical Union.

• Science

The new planets could provide a breakthrough in understanding how planets form and why there are so many “sub Neptune” worlds in our galaxy.

• Health

The United States has dug itself into a huge life expectancy hole, and not just because of the coronavirus.

• Science

Aliens are having a moment. But the evidence says all possibilities remain in play, including the possibility that we are alone.

• Science

Two NASA space telescopes teamed up to scrutinize a distant galaxy and found a clue to the potential origins of supermassive black holes.

• Reader Q&A

The Post spent a year examining the decline in U.S. life expectancy. Our reporters answered your questions about the series.