Instructions: Make a copy of the last page to hand out to students. Show the slides that follow and ask students to match up the picture to its label. Lead into a discussion about convection. Have students volunteer to read the slides aloud to improve their reading and speaking skills.

Can you match these pictures to their captions? Solar gases - Sun Lava flow - Earth Fire – Earth Coronal emission - Sun Prominence – Sun Photosphere-Sun Sunspot - Sun Eye of Sauron (Lord of the Rings movie) B C D E F G H

Matching Answers: Solar gases - B Lava flow – Earth = D Fire – Earth = A Coronal emission = C Prominence – Sun =F Photosphere-Sun = E Sunspot = G Eye of Sauron (Lord of the Rings movie) = H What do these pictures have in common? A B C D E F G H

What do these pictures have in common? CONVECTION Convection is the transfer of energy by the physical movement of matter. (Can’t work in a vacuum or zero-gravity– so the Sun’s energy radiates to us through space– doesn’t convect.) 1. This process transports (moves) energy from a lower, hotter region to a higher, cooler region. A bubble of gas that is hotter than its surroundings expands and rises. When it rises, it gives up its energy to its surroundings and is replaced by cooler material from above. Convection can only occur when there is a big decrease in temperature with height, such as is found in the Sun's convection zone. This motion of a gas or liquid is known as a convection current. C D E F G

What do these pictures have in common? CONVECTION Convection is the transfer of energy by the physical movement of matter. 2. Convection currents are common in the Earth’s atmosphere. Birds and gliders use them to stay up in the atmosphere; the convection currents are known as thermals. Convection currents can also occur in a cup of tea. They help to cool the tea because hot tea rises to the top of the cup and gives up its energy to the surrounding (colder) air. C D E F G

What do these pictures have in common? CONVECTION Convection is the transfer of energy by the physical movement of matter. Note that convection needs gravity to be able to work - you can't get convection without it. If you think that's pretty obvious or irrelevant, consider the problem of sleeping astronauts. When we breathe out, our breath contains a higher concentration of carbon dioxide (CO2) than the air we breathed in. When we are asleep and lying still, the CO2 is usually carried away into the surroundings by convection currents driven by the heat from our bodies. In a spacecraft, with a so-called 'zero-gravity' environment, no convection will occur in the spacecraft 'atmosphere' and a sleeping astronaut will soon become surrounded by air with an ever-rising concentration of CO2. That could very quickly become serious - possibly fatal! As a result, astronauts always have to sleep with a fan nearby to create the air circulation that convection would normally take care of.    C D E F G

What do these pictures have in common? CONVECTION Convection is the transfer of energy by the physical movement of matter. This process transports energy from a lower, hotter region to a higher,    4. Convection Zone   A layer in a star in which convection is the main way in which energy is transported outward. The Sun’s convection zone is a region inside the Sun which stretches from a distance of 70% of the radius from the centre outwards to just below the photosphere. C D E F G

What is this?

What is this? Moon Sun The Moon is passing in front of the space telescope’s view of the Sun. The Sun’s granulation (convection cells) are outlined, like bubbles. The cooler parts are the darker outlines of the “bubbles.” Yellow is not the real “color,” but it makes this easier to see.

Sun Convection Cells Hinode's Solar Optical Telescope is the first space-borne instrument to measure the strength and direction of the sun's magnetic field in the sun's low atmosphere, also called the photosphere. This image from the Solar Optical Telescope shows a greatly magnified portion of the solar surface. Energy from below the surface of the sun is transported by convection and results in the convection cells, or granulation, seen in this image. The lighter areas reveal where gases are rising from below, while the darker "intergranular lanes" reveal where cooler gases are sinking back down. Photosphere activity– rising and falling gases in these convection cells. Image credit: Hinode JAXA/NASA/PPARC

What other examples can you find of CONVECTION Plate tectonics… Convection is the transfer of energy by the physical movement of matter. C D E F G

What other examples can you find of CONVECTION? G

Name: ________________ Match up these labels to the pictures: ____Solar gases – Sun ____Lava flow – Earth ____Fire – Earth ____Coronal emission – Sun ____Prominence – Sun ____Photosphere-Sun ____Sunspot – Sun ____Eye of Sauron (Lord of the Rings movie)