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The sun has entered a 'lockdown' period, which could cause freezing weather, famine

Our sun has gone into lockdown, which could cause freezing weather, earthquakes and famine, scientists say.

The sun is currently in a period of "solar minimum," meaning activity on its surface has fallen dramatically.

Experts believe we are about to enter the deepest period of sunshine "recession" ever recorded as sunspots have virtually disappeared.

Astronomer Dr. Tony Phillips said: "Solar Minimum is underway and it's a deep one."

"Sunspot counts suggest it is one of the deepest of the past century. The sun's magnetic field has become weak, allowing extra cosmic rays into the solar system."

"Excess cosmic rays pose a health hazard to astronauts and polar air travelers, affect the electro-chemistry of Earth's upper atmosphere and may help trigger lightning."

NASA scientists fear it could be a repeat of the Dalton Minimum, which happened between 1790 and 1830 — leading to periods of brutal cold, crop loss, famine and powerful volcanic eruptions.

Temperatures plummeted by up to 2 degrees Celsius (3.6 degrees Fahrenheit) over 20 years, devastating the world's food production.

On April 10, 1815, the second-largest volcanic eruption in 2,000 years happened at Mount Tambora in Indonesia, killing at least 71,000 people.

It also led to the so-called Year Without a Summer in 1816 — also nicknamed "eighteen hundred and froze to death" — when there was snow in July.

So far this year, the sun has been "blank" with no sunspots 76 percent of the time, a rate surpassed only once before in the Space Age — last year, when it was 77 percent blank.