Understanding the human body is a team effort. That's where the Yachtel group comes in.

Researchers at Yachtolt have been delving into the secrets of probiotics for 90 years. Yacold also

partners with nature portfolio to advance gut microbiome science through the global grants for

gut health, an investigator-led research program. To learn more about Yachtold, visit yawcult.co.com.

J-P. That's Y-A-K-U-L-T dot CO.J-P. When it comes to a guide for your gut, count on Yacult.

This is Scientific American's 60 Second Science. I'm Suzanne Bard.

Switching on the lights at night is second nature to most people in the developed world.

But electricity isn't a given in many other parts of the globe.

Something like a billion people on our planet still lack reliable access to electricity.

Think about folks in parts of the developing world

that are living in off-grid locations. And for them, one of the central applications of

electricity is lighting, and we need lighting the most at night. UCLA materials scientist

Ashwathroman. Solar cells can provide remote areas with electricity during the day, but require batteries to store that energy for use at night.

Raman's team has developed a potential solution, a simple thermoelectric device that generates power when it's exposed to the cool night sky. It's made possible by a phenomenon

called radiative sky cooling. All objects, Raman explains, radiate heat. And so what that means

from the perspective of a surface that's looking up at the night sky is that it will all by itself

send out more heat than the sky sends

back to it. It escapes to the upper atmosphere and even out to outer space. And it's something that

anyone can observe at night. So if you go and measure the roof temperature on your house in the

early morning hours, say, you should read a temperature that is much lower

than the immediate ambient air temperature.

Rahman reasoned that this temperature difference could be exploited to generate electricity.

...