Sunspots and Geomagnetic Storms

Name: _________________________________       Date: _____________

Can events that happen on the Sun 93,000,000 miles away really have an effect on Earth? You've probably seen pictures of sunspots. Although they appear as small dots on the solar surface, they can have a surprisingly strong effect on what is known as "space weather."

In this activity you'll find out what sunspots are, when they occur, and how they affect both space weather and life here on our home planet.

1. To begin, go to NASA's Sunspots page. What are sunspots?
   
   
   
   
2. Where is the magnetic field strongest within a sunspot?
   
   
   
   
3. Next, you'll find out about the Sunspot Cycle.
   1. What do monthly averages show about the number of sunspots?
      
      
      
      
   2. How long is the solar cycle (in years)?
      
      
      
      
4. Look at the graph of Sunspot Number to the left of the text. It shows the average daily number of sunspots for a given year.
   1. When was the last peak of sunspot activity?
      
      
      
      
   2. What was the sunspot number at the last peak of activity?
      
      
      
      
5. Based on your answers to questions 3 and 4, when will the next peak of the cycle occur?
   
   
   
   
6. In what year will the current cycle reach its low point (minimum)?
   
   
   
   
7. To find out what effect sunspots have on our space weather, visit the Space Weather Bureau and read today's solar report. Summarize today's news about the Sun in the What's Up in Space column.
   
   
   
   
8. Sunspots have been linked to both solar flares (fiery "storms" in the Sun's atmosphere) and streams of hot, charged particles that are carried away from the Sun in the solar wind. When they reach Earth's atmosphere, these particles can trigger disruptive geomagnetic storms. Look at the top of the left column and find today's reading of the solar wind. What is today's wind velocity? What is the density of protons in the solar wind?
   
   
   
   
9. Continue scrolling down the left column to today's (or the most recent) sunspot number. What is it? How does this number compare to your daily average estimate for the year 2000 in question 3?
   
   
   
   
10. Scroll further down the column to the photo of the Sun showing current active sunspots. Summarize the report of current activity (just below the photo.)
    
    
    
    
11. Keep scrolling to the current image of coronal holes. Click on the glossary link that explains them. What is the connection between coronal holes and the solar wind?
    
    
    
    
12. A bit further down the left column, you'll see NOAA forecasts for solar flares. What is the probability of medium-sized (M-class) and major (X-class) flares over the next 24 and 48 hours?
    
    
    
    
13. Finally, scroll to the geomagnetic storm forecast. Click on the glossary links explaining the three categories (active, minor storm, major storm). What is the probability of each kind of geomagnetic storm over the next 24 and 48 hours? (Give values for both mid- and high-latitudes.)