Earth may be headed into a mini Ice Age within a decade

Physicists say sunspot cycle is 'going into hibernation'

Good news for Mars astronauts – Less good for carbon traders, perhaps

Hill's own research focuses on surface pulsations of the Sun and their relationship with sunspots, and his team has already used their methods to successfully predict the late onset of Cycle 24.

"We expected to see the start of the zonal flow for Cycle 25 by now," Hill explained, "but we see no sign of it. This indicates that the start of Cycle 25 may be delayed to 2021 or 2022, or may not happen at all."

Hill's results match those from physicists Matt Penn and William Livingston, who have gone over 13 years of sunspot data from the McMath-Pierce Telescope at Kitt Peak in Arizona. They have seen the strength of the magnetic fields which create sunspots declining steadily. According to the NSO:

Penn and Livingston observed that the average field strength declined about 50 gauss per year during Cycle 23 and now in Cycle 24. They also observed that spot temperatures have risen exactly as expected for such changes in the magnetic field. If the trend continues, the field strength will drop below the 1,500 gauss threshold and spots will largely disappear as the magnetic field is no longer strong enough to overcome convective forces on the solar surface.

In parallel with this comes research from the US Air Force's studies of the solar corona. Richard Altrock, in charge of this, has found a 40-year decline in the "rush to the poles" – the poleward surge of magnetic activity in the corona.

"Those wonderful, delicate coronal features are actually powerful, robust magnetic structures rooted in the interior of the Sun," Altrock says. "Changes we see in the corona reflect changes deep inside the Sun ...

"Cycle 24 started out late and slow and may not be strong enough to create a rush to the poles, indicating we'll see a very weak solar maximum in 2013, if at all. If the rush to the poles fails to complete, this creates a tremendous dilemma for the theorists ... No one knows what the Sun will do in that case."

According to the collective wisdom of the NSO, another Maunder Minimum may very well be on the cards.

"If we are right," summarises Hill, "this could be the last solar maximum we'll see for a few decades. That would affect everything from space exploration to Earth's climate."

The effects on space exploration would be benign, as fewer or no solar storms would make space a much less hostile environment for human beings. At the moment, anyone venturing beyond the Earth's protective magnetic field (the only people to have done so were the Apollo moon astronauts of the 1960s and '70s) runs a severe risk of dangerous or fatal radiation exposure during a solar storm.

Manned missions beyond low Earth orbit, a stated aspiration of the USA and other nations, might become significantly safer and cheaper to mount (cheaper as there would be no requirement for possibly very heavy shielding to protect astronauts, so reducing launch costs).

The big consequences of a major solar calm spell, however, would be climatic. The next few generations of humanity might not find themselves trying to cope with global warming but rather with a significant cooling. This could overturn decades of received wisdom on such things as CO2 emissions, and lead to radical shifts in government policy worldwide. ®

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