4/28 & 4/29 - 8th Grade Agenda Learning Objective: Learn about the sun Collect HW: Reading & Notetaking p.238 – 240 Solar System Lab Video: When we left Earth Textbook Reading: p.538 - 550 HW: Review & Reinforce p59 & p 60

Daily Reflection Prompt: Write 3 facts about the sun.

In what units do we measure distances around our solar system ? AU (Astronomical Unit) 1 AU = Distance between the sun and the Earth 1 AU = 93 Million Miles

In what units do we measure distances between the stars ? Light Year Light travels about 186,000 miles per second 1 Light Year = 65,000 AU 1 Light Year = 6 Trillion Miles Closest Star (Alpha Centari) is about 4.3 Light Years away

How much of the solar system’s mass is in the sun? About 99.8% Most of the mass of the solar system is in the sun

How does the sun generate it’s energy? Nuclear Fusion Hydrogen Atoms join together to from Helium Some of the matter is converted into energy The Sun’s core reaches about 15 million degrees Celsius

The sun’s atmosphere has three layers Ph___sphere, the Ch____sphere and the C_____ oto romo orona Photosphere: Inner Layer (Generate most of the light) Chromosphere: Middle layer (reddish) Corona: Outer layer (Looks are a crown)

Layers of the Sun

Sun S____ pots Sunspots look small. But they are larger than Earth. Sunspots are areas of gas on the sun’s surface that are cooler than the gases around them. This is why sunspots look darker than the rest of the photosphere. Sunspots intensifies every 11 years

Solar Fl____ ares Solar Flares are eruptions on the sun Releases large amounts of magnetic energy. Can cause electrical problems here on Earth

Features of the sun Nuclear Fusion Hydrogen Atoms join together to from Helium Some of the matter is converted into energy The Sun’s core reaches about 15 million degrees Celsius

Mercury Smallest Planet Closest to the Sun It has almost no atmospheres Surface temperature is 430C to -170C

Mercury

Venus Atmospheric Pressure is 90 X greater than Earth Clouds are made of sulfuric acid Atmosphere is carbon dioxide Surface temperature is 460C

Venus Surface of Venus. Pictures taken by the Russian Venera-13 probe in 1982. It lasted only a couple of hours on the Venusian surface

Mars Atmosphere is 95% carbon dioxide Large amount of liquid water flowed on the Mar’s surface in the distant past. There are giant volcanoes Surface temperature is -140C to 20C