250,000 liters: the volume of water a single, mini-fridge-size Slingshot machine purifies in one year. That’s enough for about 300 people. Slingshots are able to purify even seawater and sewage.

288: the number of times a day this experimental bionic pancreas checks the blood-sugar level of its wearer.

60 hours: how long it took Popular Science contributing writer Douglas Main to travel to the Tambopata Research Center in Peru. There, he learned about the latest research into newly discovered, decoy-building spiders.


Reeves transferring a spider from a vial to a box with clear sides, to observe its web-building process. Afterward all the spiders were returned to the jungle.

1 kilometer: the height of the taller of two hot pink towers developers are planning for Wuhan, China. The towers will feature eco-friendly technology such as solar panels, a wind turbine and rainwater collectors.

The world’s tallest building may just be its pinkest.

2: knighthoods Queen Elizabeth II bestowed this week to physicists involved in the detection of the Higgs boson.

7: the number of pins in the Popular Science map of where driverless cars have driven with regular traffic.

18: the number of black-footed ferrets that scientists captured in Wyoming in 1980. The ferrets were the last of their kind and the only ancestors to all of the black-footed ferrets living today.

Proud Parent

A black-footed ferret and kits!

695,000 square miles: the area by which Obama Administration pledged to expand the Pacific Remote Islands Marine National Monument. When the expansion goes through, the monument will cover about 782,000 square miles and will be the largest reserve on Earth.

2030s: the time when Japan may first fly homegrown stealth fighters.