The Sun goes through an 11 year sunspot cycle, where it starts out with no sunspots at all on the disk. Then the spots begin to appear and then there are lots of spots, and then the number begins to diminish until there are no spots at all. Cycle 24 peaked in 2014 and then the number of spots decreased and about 3 years ago, there were no spots at all. That has lasted until now, and a few spots have started to appear in the last few months. This is the start of Cycle 25. The other day, this complex of sunspots came around the limb of the sun and started across the face. This group will be in view for about 7 days and will probably change some. Some spots may get larger and others may get smaller and disappear. An amazing thing to watch the Sun. The detail below shows the sunspot group enlarged - please click on it to see more detail.
Ken, I am curious, what exactly are these spots and what do they mean?
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I am confused. I thought you were photographing and measuring sun spots a year or two ago. Now you are talking long cycles.
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I looked up photos on my laptop to see when we visited you in the summer. You had your telescope set up outside. It was 2016! Doesn't seem possible! It is incredible that you can see the sun spots! truly amazing!! betsey
ReplyDeleteHi Ron: Good question! The Sun is a ball of incredible magnetic activity, in addition to all the nuclear reactions going on. Sunspots are temporary phenomena on the Sun's photosphere that appear as spots darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. They look like holes in the surface that you could fall into, but they are just cooler areas. As for their significance, it is just something that happens to stars while they burn. There is the 11 year cycle, and two 11-year cycles make up a 22 year cycle, and when that happens, believe it or not, the Sun reverses its polarity, so if north was the top, like in a bar magnet, suddenly north is on the bottom and south is on top. The Sun doesn't physically turn upside-down, it is just the positive and negative poles reverse. It is astounding how much scientists have learned about the Sun since we have to learn everything from a distance of 93 million miles! Well, OK, to be technical, we do have satellites that we sent much closer to the Sun to study it, but we learned a lot just from here on Earth, before we sent satellites much closer.
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