The Sun goes spotless

Image 1 of 4

The sun spent a 2 week period without a spot... something that's pretty rare.  Image courtesy of NASA

Our nearest star just recently experienced 2 straight weeks of spotless conditions on its way toward an 11-year cycle low.  A sunspot is an area of slightly cooler conditions that forms on the surface of the sun.  Many of these spots are dozens of times bigger than the Earth itself, but are typically small when compared to the massive nature of the sun.  They appear as dark red areas around the sun, a similar color when lava here on Earth begins to cool, versus the very bright red color of lava that is fresh from the ground and flowing freely. 

Very little is known about how and why these form, but most scientists seem to agree that they are caused by interactions with its own magnetic field.  These spots occur over regions with intense magnetic activity, and when that energy is released, it gets launched into space.  These are called solar flares, or coronal mass ejections.  When these flares head toward Earth they can cause a host of problems with communication, satellites, and even power outages if they are large enough.

What is considered to be scientific fact is that sunspots go on a roughly 11-year cycle.  Right now we are on recorded solar cycle 24… and heading into the sunspot minimum of that cycle, which is likely why the sun experienced 2 straight weeks without a spot, something quite rare.  This cycle is also the smallest sunspot cycle in more than a hundred years.  But there also maybe other solar cycles, but isn’t considered scientific fact because the amount of useable data is just too low.  Some scientists believe there is also an 87-year cycle and a 200-year cycle.

Even though these sunspots are cooler areas on the sun, they can cause the opposite conditions here on Earth as they send their solar storms in our direction.  While this is just a scientific theory, and in no way of being proven anytime soon, the history and cycle of sunspots may give us some clues on how and why are climate is the way it is.  If you look at the graph above of the last 400 years of recorded sunspots, there have been some big changes over the last couple hundred years.  There are 3 general periods starting with the Maunder minimum, in the 1600’s and early 1700s, followed by the Dalton minimum in the early 1800s, and then the 20th century Modern Maximum.  What’s interesting about this is it correlates pretty well with overall global climate, at least with the records we already know… the same ones that may not be all that reliable.  But, we know that there was a much cooler period called the Little Ice Age ranging from the 16th to 18th centuries… followed by a cooler period in the mid to late 1800s… and then again in the 1960s and 1970s.  Clearly, these time frames don’t line up exactly, but there may be some sort of correlation there.  Now, there are MANY hundreds or even thousands of other factors at play here on Earth, but it is still interesting to note and something to keep an eye on going forward, especially if we may be going into a down period for sunspots.  Hopefully our science will improve enough over the next few decades that we eventually know for sure how these different sun cycles effect climate here on Earth.