Science & technology

Aerial surveillance
The spy in the sky that sees backwards in time

Use of wide-area motion imagery is spreading

Grid inertia
Green power needs more than just solar panels and wind turbines

Electricity grids themselves must be tweaked to cope

Now hear this
GPS for the oceans

A system based on sound waves could transform marine biology

East Coast Fever
A genetic discovery could help fight an African cattle disease

That may allow the introduction of higher-yielding breeds

Rocket Lab’s grab
Another rocketry firm experiments with recycling its launchers

If it is successful, it will make getting to orbit cheaper still

Human space flight
Spacesuits are showing their age

Astronauts’ wardrobes are in need of a makeover

Launch break
America is ending anti-satellite missile tests

No one wants Kessler syndrome. But will other countries follow suit?

Out, dammed spot
A sound way towards reversible vasectomies

Researchers test a means to block—and neatly unblock—men’s reproductive ductwork

Light entertainment
Why 15,000-year-old art might have been displayed in firelight

Markings on prehistoric art hint at an early attempt at animation

Twists and turns
How balls of blackworms avoid the knotty step

Thousands of them can disperse in thousandths of a second