NASA Goddard: Solar Cycle Primer
This tutorial features a 3 minute video alongside a beginner's "Primer" on the sunspot cycle. The exact length of the cycle can vary, but it averages approximately 11 years from one solar maximum to the next. This tutorial is especially relevant because we're coming into another solar minimum phase, expected to hit its lowest values sometime in 2019. Teachers: If Earth experiences another lengthy solar minimum, such as the Maunder Minimum from 1645-1715, weather patterns across the globe could change to result in cooler weather. While this could help mitigate some effects of global warming, it could lull people into believing (wrongly) that climate change has been reversed.
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NOAA Space Weather Prediction Center
For the student who asks, "Why should I care about sunspots?" here's a robust set of images and informational tidbits. "Space Weather" describes magnetic activity and ejection phenomena originating on the sun that impact systems and technologies on Earth or on man-made satellites near Earth. The frequency of solar flares, for example, is directly correlated with the number of active sunspots on the sun. We are currently very near a Solar Minimum, when fewer sunspots are generated. This fact-packed page  provides great answers to why we should care about solar weather events.
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Earthsky.org: What is the Ecliptic?
Here's another great article by astronomer Christopher Crockett, written to help novice learners understand what is meant by the "path of the ecliptic". The ecliptic is an imaginary line in the sky that shows the apparent path of the sun's motion, as seen from Earth. All the planets in our solar system orbit around the sun along this imaginary ecliptic plane (except Pluto, which is arguably not a planet). This coordinate system is very different from the "celestial sphere" framework, which places Earth at the center of the universe. The article will help students realize why reference frames are so crucial in astronomical measurement and observation.
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Exploratorium: Sunspots - History
This free online tutorial presents information about how ancient civilizations viewed sunspots, takes a concise look at the first rudimentary telescopes, and explores the contributions of Galileo, Scheiner, Herriott, and Fabricius. It includes historic drawings of sunspot cycles.
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The Galileo Project: Sunspots
This background information piece on sunspots is part of a comprehensive digital collection on Galileo, compiled by Rice University History department. It goes into detail on what happened when Galileo came across drawings by Christoph Scheiner, a Jesuit mathematician who was observing sunspots through a telescope equipped with colored glasses. Scheiner believed that sunspots were "satellites" -- near, but not on, the sun's surface. Galileo disagreed, theorizing that sunspots were phenomena occurring on the sun's surface.
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Exploratorium: Sunspots - Modern Research
This interactive resource looks at how newer research methods for examining the sun are changing our understanding of sunspots. It explores our expanding knowledge of the structure of sunspots, the sunspot cycle, and how geomagnetic events on the sun can affect Earth.
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