Natural Sciences and Technology Grade 6 Term 4: Planet Earth and Beyond The Solar System (ppt 1)

Natural Sciences and Technology - Grade 6 Topic 1 The Solar System The Sun Natural Sciences and Technology - Grade 6

Natural Sciences and Technology - Grade 6 The Sun Natural Sciences and Technology - Grade 6

Natural Sciences and Technology - Grade 6 Introduction The Sun is at the centre of the Solar System. The solar system is made up of celestial bodies called stars, planets, asteroids and meteorites. Celestial bodies have mass and are made up of rock, gas or both. Earth is a planet in the Solar System. These are introductory points. You can smoothly transition by stating that as young astronomers (people who study the skies) they will first explore the sun. Provide them with the worksheets entitled “Solar System Journey” ask the learners to make notes as they explore. When they have completed this worksheet they will be able to compare the stars and planets and you can assess their knowledge. Celestial Body = object in space with mass Mass = amount of atoms in an object Natural Sciences and Technology - Grade 6

Natural Sciences and Technology - Grade 6 The Sun is: the centre of our Solar System. a medium-sized star. medium-hot and yellow. a ball of gas held together by gravity. made up of six layers. 420 times larger than Earth. The word “solar” means “of the sun”. The Sun is a star because it produces its own energy (Forms of energy released include light, heat, and various rays, like X rays and gamma rays, which are forms of radiation). Gravity = a force of attraction between objects. The sun is made up of gasses. The most abundant gas is Hydrogen. Hydrogen is undergoing fusion to make Helium, which releases a huge amount of energy. Natural Sciences and Technology - Grade 6

Natural Sciences and Technology - Grade 6 Anatomy of the Sun Structure or anatomy of the Sun The energy comes from gasses that are squeezed together (hydrogen gas turns into helium). The Sun is very hot so never look directly into the sun, because your eyes can be damaged. Chromosphere (Surface) The surface is about 5500 0C. The surface/atmosphere is a thin layer of gas. See sun spots and explosions. Core Hottest Part of the Sun. About 15 million 0C in the centre. Corona = halo of light energy cannot be seen with the naked eye only when there is a full eclipse. (will learn about that later – remember do not look at the sun even during an eclipse). Photosphere – where light and other forms of energy are released. Convective Zone – heat transfer area (heat released). Radiative = heat emitting zone. Core heat is produced and it is the hottest because of gravity it is the highest and closer to the centre. Natural Sciences and Technology - Grade 6

Natural Sciences and Technology - Grade 6 The Surface Sun Spots Sunspots are darker, cooler areas on the surface of the Sun. Sunspots have temperatures of 3,800 K [Kelvin]. Solar Flares It is a sudden flash of the Sun’s increased brightness, which is usually observed near its surface. On the surface there are cooler spots that appear like dark spots = sun spots. Sun flares are explosions on the surface of the Sun. Natural Sciences and Technology - Grade 6