The sun appears to travel through the sky in a predictable daily pattern, an arc.
It might be nice to take a Panoramic photo of the southern sky during each visit outside to show the sun's apparent path over the day. Also, set up the telescope and backboard to observe sunspots for the Mini-Lesson.
Watch the two videos below and discuss them.
| || |
Why does the sun rise and set each day?
Use this Science Mystery (free subscription required) to help students understand why the sun appears to rise and set each day: https://mysteryscience.com/astronomy/mystery-1/day-night-earth-s-rotation/73?r=6994723#slide-id-0
Mini Lesson: Sunspots
The Sun looks very different close up. Not only does it look like a gigantic fireball, but it is also very spotty. Can you guess what these spots could be? Sunspots is the answer! But far from having a skin problem, these dark regions have quite a different meaning. Sunspots are much cooler than the rest of the Sun and are made from what is known as magnetic activity. These areas have the strongest magnetic activity. You may have noticed that magnets love sticking to metal objects but are not so keen on other things like wood. The second thing that you might have noticed, is that they have an “N” and an “S” written on them. Do you know what these letters stand for? That’s right, the “N” stands for “North” and the “S” means “South” and they are called the poles of the magnet.
Sunspots are huge and act just like poles. Because there needs to be a “North” sunspot and a “South” sunspot, these spots like to appear in pairs. On your mission, you should be able to see them in pairs or in groups - they are rarely seen on their own! If you look closely from your spacecraft, you might be able to see two sunspots attached to a bright loop of hot gas. This loop is called a solar prominence and such features appear because of the magnetic field of the Sun. Sunspots are also responsible for bright bursts from the surface called solar flares and the more there are, the brighter the Sun appears!
Sunspots are self-perpetuating storms, similar in some ways to Earthy hurricanes. Sunspot activity cycles about every ten years (7.5 - 11). The point of highest sunspot activity during this cycle is known as Solar Maximum (Solar Max for short), and the point of lowest activity is Solar Minimum (Solar Min). (2016-2017 is around the time of Solar Minimum.) Sunspots are relatively easily observed -- a small telescope with a projection facility suffices. Note: Never look directly into the Sun; Galileo's eyes did not survive this, and yours will not either (he went blind).
Sunspots are cooler than the rest of the Sun, but many scientists think that when there are a lot of sunspots, the Sun actually gets hotter. This affects the weather here on Earth, and also radio reception. Without sunspots the Earth would probably be cooler. In the same way, if there were too many sunspots, the Earth would get really hot, and there would not be a lot of rain. This would make lots of droughts on the Earth. Droughts are a long time with no rain. When it does not rain, the plants die: when the plants die, many animals die too. A drought can be a very dangerous thing. The sunspots help keep Earth the right temperature. Scientists study sunspots and other solar phenomena, so they can know what they do to Earth.
Create Your Video:
- Explain that the sun appears to travel in an arc across the sky every day using models and clear explanation.
- Explain that the apparent motion of the sun is actually caused by the earth's rotation on its axis.
- Explain why the position of the sun’s arc varies throughout the year.
| || |