The Sun follows cycles of roughly 11 years where it reaches a solar maximum and then a solar minimum.
The last time there was a prolonged solar minimum, it led to a ‘mini ice-age’, scientifically known as the Maunder minimum – which lasted for 70 years.
During a solar maximum, the Sun gives off more heat and is littered with sunspots. The sun gives off less heat in a solar minimum due to a decrease in magnetic waves.
Currently, we are in the solar maximum, but in 2021 or sooner, the temperatures given off from the Sun will begin dropping as we enter the solar minimum.
This year, scientists have observed 60 percent fewer sunspots than the same period in 2017 as the Sun prepares to enter the cooler cycle.
SpaceWeather.com says sunspots are “vanishing faster than usual” and warns there have been “whole weeks going by without sunspots”.
The website continues: “The fact that sunspots are vanishing comes as no surprise. Forecasters have been saying for years that this would happen as the current solar cycle (‘solar cycle 24’) comes to an end. The surprise is how fast.”
The National Oceanic and Atmospheric Administration (NOAA) said: “Solar cycle 24 is declining more quickly than forecast.
“The smoothed, predicted sunspot number for April-May 2018 is about 15.
“However, the actual monthly values have been lower.”
If the solar minimum has begun early, it could lead to a cold snap on Earth.
The Maunder minimum began in 1645 and lasted through to 1715, where sunspots were exceedingly rare.
During this period, temperatures dropped globally by 1.3 degrees celsius leading to shorter seasons and ultimately food shortages.