The sun is very important to life on earth. It provides light and warmth, helps drive the ocean currents and our weather, drives photosynthesis and plant life and its gravity keeps us from flying out into the depths of space.
But the sun can also be a bit of a headache sometimes.
The surface isn’t static and it isn’t calm by any means. There are cycles and tides and shifts on the sun that can affect the nearest planets, earth being one of them.
The biggest troublemakers are sun spots. They are “cooler” areas on the sun’s surface – they range between 4,500 - 8,000 degrees Fahrenheit compared to the normal 10,000 degrees of the sun’s surface.
But that’s not all they do. Sunspots are the focus of some very intense magnetic activity. Some of the magnetism can get so strong that it causes parts of the sun to erupt off the surface (called a coronal mass ejection or CME) and blast out into space. When those particles interact with the earth’s magnetic field they cause the aurora borealis and aurora australis at the poles.
While normally held to the polar regions of either hemisphere, when the big flares hit the earth the auroras can be seen as far south as New York City and Denver. CMEs generally just put on a light show for those lucky enough to see them and might cause some radio static.
But these solar storms are miniscule to the true power that the sun has to unleash. Some storms, like in the 1859 Carrington Event, are powerful enough to cause electric wires to spark on the earth’s surface. In that solar storm the auroras were reported as far south as the Caribbean and sparks from telegraph wires shocked operators and set telegraph offices on fire.
If a CME of that magnitude hit the earth today it is likely that nearly every electronic device would suffer some sort of short or damage. In addition many power stations would likely suffer some significant damage and a majority of the power grid could be shut down.
There is some good news though. First off, those extreme solar storms are exceedingly rare. In addition, the earth does a very good job of protecting itself from these solar storms which have been happening since the sun was born about 4.6 billion years ago.
The earth is protected by its very strong magnetic field which both enables compasses to work and deflects much of the radiation from our sun and the universe away from its inhabitants. Some of that radiation and some charged particles from the sun make it to the earth’s upper atmosphere where it interacts with oxygen and nitrogen molecules in the upper atmosphere producing the auroras.
The good news is our magnetic field is so strong that the majority of the flares don’t affect anyone on the surface. In addition the relatively miniscule size of the earth works to our advantage when it comes to dodging the solar flares.
According to space.com the sun is about 108 times larger than the earth and could contain about 1.3 million earths inside it. That’s pretty big.
In addition, the earth is about 93 million miles away from the sun. And it’s moving around the sun at about 67,000 miles per hour according to Cornell University.
All that makes the earth a very small moving target to hit, even with a shotgun style solar flare.
The sun has to perfectly time the flare and get it on the correct plane for the flare to hit the earth. That’s why, even though flares aren’t particularly rare, they don’t affect the earth very often.
Unfortunately, right now there really isn’t much we can do to protect our electronics from the truly massive solar flares. But you can keep track of when the flares are likely and even get the chance to see the northern lights when they do happen on websites like spaceweather.com.
More good news is that astronomers are predicting that the sun is on its way down from its solar maximum. That means that the sunspots are diminishing in number and solar activity should eventually peter out. Then it is about 22 years until the next solar maximum when sunspot activity will slowly increase towards 2036.