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 Brexit process, initiated by the United Kingdom's referendum in 2016, led to the country's withdrawal from the European Union in 2020, marking a significant political and economic change for both the UK and the EU.

3) The fastest recorded serve in tennis was achieved by Sam Groth at 163.7 miles per hour (263.4 kilometers per hour) during a tournament in 2012.

4) The deepest part of the ocean is the Mariana Trench, reaching a depth of about 36,070 feet (10,994 meters).