Data and Activities for Solar Learning (DASL) provides a classroom learning environment based on a twenty-five year record of solar magnetograms from the National Solar Observatory (NSO) at Kitt Peak, AZ. The data, together with image processing software for Macs or PCs, can be used to learn basic facts about the Sun and astronomy at the middle school level, to study properties of the Sun's magnetic cycle with classroom exercises emphasizing data and error analysis at the high school level, and to participate in a new scientific study, Research in Active Solar Longitudes (RASL), in collaboration with classrooms throughout the country and scientists at NSO and NASA. The students use ImageJ macros that have been developed to explore and research the 25 years of NSO/Kitt Peak magnetogram data.

Included within these teacher pages are a pre/post-test for your students, information concerning the National Science Teaching Standards and how they apply to the DASL program and user's guides that walk you through each of the included lessons.

• Pre/Post-Test of student assessment (also available in pdf format)
• National Science Teaching Standards and DASL
• ImageJ Toolbar
• Lessons
  • Aphelion and Perihelion Part 1 (Middle to High School - 30 minutes) - Aphelion is the point in its orbit when the Earth is farthest from the Sun; perihelion is the point when it is closest. In this lesson your students will construct a movie of solar magnetogram images to estimate the approximate dates of aphelion and perihelion from the relative sizes of those images.
  • Aphelion and Perihelion Part 2 (Middle to High School - 1 to 2 hours) - The dates of aphelion and perihelion can be more accurately determined with the graphical analysis described in this lesson with pairs of students working collaboratively.
  • Constructing a Maunder Butterfly Diagram (High School - 1 hour) - The Maunder butterfly diagram is a plot of the latitude on the sun where sunspots first appear. Early in a sunspot cycle, the spots appear at higher latitude. Later in the cycle, they appear nearer the equator. This lesson is a nice collaborative effort by a class to construct this classic tool of the solar astronomer.
  • Finding the Eccentricity of Earth's Orbit (Middle to High School - 30 minutes or less) - Kepler's first law of planetary motion states that a planet's orbit is an ellipse with the sun at one focus. Your students will determine just how eccentric that orbit is with the calculations they'll perform in this follow-up activity to the lesson Aphelion and Perihelion Part 2.
  • Illustrating Joy's Law (High School - 1 hour) - Joy's law illustrates the inclination of sunspot bipoles and so will your students with this activity mapping leading and trailing edges of active regions.
  • RASL (Middle to High School - 1-2 hours) - Researching Active Solar Longitudes will allow your students to map longitude data for active regions on the solar surface and submit it for inclusion in a national research project.
  • Solar Rotation Calculations (High School Advanced and Medium - 1 to 2 hours) - The sun does not rotate as a solid body. This difference in rotation rates is known as differential rotation and can be seen when equatorial structures rotate more rapidly than polar features. Your students will be able to determine the rotation rate of active regions on the sun and make comparisons from latitude to latitude and solar rotation to solar rotation.
  • Stoneyhurst Disk Animation (Middle to High School - 30 minutes or less) - Visualize the change in position of structures on the surface of the sun throughout the year with this simple QuickTime movie activity.