The Voyager probes are still talking, and the signal keeps getting quieter
Launched in 1977, both Voyagers now report from interstellar space using a transmitter weaker than a fridge bulb. Engineers switch off instruments one at a time to stretch the remaining power.
Why robots still struggle to fold laundry
Moravec’s paradox says that tasks we find hard, like chess, can be easy for machines, while tasks we find trivial, like folding a shirt, are brutally hard.
A teaspoon of neutron star would weigh about as much as a mountain
Neutron stars pack more than the mass of the Sun into a ball roughly the size of a city. Their matter is so dense that a sugar-cube sample would weigh around a billion tonnes.
Space elevators: the hard part is the cable
A tether from the equator to geostationary orbit would make getting to space cheaper than flying, if anything were strong enough to build it from.
Tardigrades survive almost anything
Boiling, freezing and even vacuum.
How skyscrapers resist the wind
Tuned mass dampers and clever shapes.
How to see the International Space Station
No telescope needed, just good timing.