William Neff

The arrival of a Chinese high-altitude balloon in U.S. airspace called for a measure of creativity and forced military planners to improvise a response.

How do balloons similar to the Chinese balloon work? How do these balloons fly? Where is China's balloon headed? We put together a visual explainer.

• Europe

The German-made battle tank may be a highly prized piece of military technology, but the logistic networks that could support it may be even more important.

• The New Space Age

Humans evolved in conditions of plentiful gravity and relatively little radiation. Space is the reverse — and it upends almost every system inside of us.

NASA wants to take us back to the moon — this time to stay. Here are the challenges we're going to have to overcome to make that happen.

• Investigations

For pro bodybuilders, biggest is best onstage. Steroid use is rampant. But creating that bulk can disrupt nearly every system in the body.

• Europe

Russia has used Iranian-made Shahed-136 kamikaze drones to strike Kyiv, prompting Ukraine to seek more advanced air defense systems.

The war in Ukraine, and threats by Vladimir Putin, have led to a resurgence of fears about Russia's nuclear arsenal.

Homeowners unable to relocate in the face of climate disasters have found innovative ways to protect their possessions.