1) The coldest known temperature in the universe was achieved in a laboratory in 2019, reaching a fraction of a degree above absolute zero (-273.15 degrees Celsius).

2) The process of nuclear fusion powers the sun and other stars, fusing hydrogen atoms together to form helium and releasing vast amounts of energy in the process.

3) The world's oldest known living tree is a bristlecone pine named "Methuselah" in California, estimated to be over 4,800 years old.

4) The unicorn is the national animal of Scotland.