1) The Northern Lights, also known as the Aurora Borealis, are natural light displays that occur in the polar regions due to interactions between the Earth's magnetic field and solar particles.

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) In Norse mythology, Ragnarok is a cataclysmic event that signifies the end of the world. It involves a series of apocalyptic battles and natural disasters, leading to the destruction of the gods and the world as it is known. From the ashes, a new world and a new generation of gods emerge.

4) The world's oldest university, Al-Qarawiyyin, was founded in 859 AD and is located in Fez, Morocco.