Activity

Sun spot observation

Summary
Use a pair of binoculars to project an image of the sun, resolving large sunspots, on a white poster board.
Science content
Earth/Space: Sun, Moon, Solar System, Universe (1, 4, 6)
Lessons activity is in
Materials
  • a pair of decent binoculars
  • a tripod/stable stand that the binoculars can be strapped to; angle of direction/focus ideally adjusted while attached
  • large cereal box and pair of scissors
  • large white foam core sheet/poster board
Procedure

Set up the binoculars as in the first image, with once eyepiece poking through the cereal box.
Stand them on the tripod about 1m away from the board.
Adjust the angle of the binoculars so that the sun's image is projected on the board, then focus so that it is clear.
If you are lucky you will see dark spots on the face of the sun.
Check http://www.tesis.lebedev.ru/en/active_areas.html to find out what you should be looking for.

Sunspots are caused by strong magnetic fields that block heat coming from the inside of the sun, which allows the region above to cool (to 3700°C). They have a darker core, "umbra", surrounded by a lighter "penumbra" and are often larger than the Earth.

They move across the surface of the visible side of the sun as the sun rotates (about once every 2 weeks/month?).
By the time that area of the sun has come around again, the sunspot activity has changed.

Notes

The sun cycles through periods of low and high sunspot activity. We are in cycle 24, heading towards a low in 2020, before activity increases again.

Grades taught
Gr 3
Gr 5
Teaching site
JEMZ+ After school science