In zero gravity, a candle's flame is round and blue.
16
A ball of glass will bounce higher than a ball made of rubber.
73
Sound travels fifteen times faster through steel than through air.
134
Scientists are learning from the 1700-year-old Lycurgus Cup, which changes colour thanks to nano particles.
0
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310