The bark of an older redwood tree is fireproof.
65
Scientists aren't sure what color dinosaurs were.
312
During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
21
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
6
One cubic foot of gold weighs more than 1,200 pounds!
78
One 75-watt bulb gives more light than three 25-watt bulbs.
57
The average temperature at 40,000 feet above sea level is -60 F.
56