1 CHAPTER 11 We continue to Learn a lot about the Solar System by using Space Exploration
2 Section 11.1 The Sun page 390 -Average sized star -Millions of km away -300,000 more massive then Earth, 99% of all mass in our solar system -Approx. 5 billon Years old with 5 billion more to go!
3 The Huge size of the sun causes pressure to build up at the center of the sun as gravity pulls the mass inward Thermonuclear Reactions turn H (hydrogen) He (helium) giving off Heat, Light and UV radiation in the process Heat, Light and UV radiation H He Pressure
4 Solar Radiation - E (energy) Emitted from the sun in the form of Electromagnetic Radiation E that is carried or radiated in the form of waves that range in length, ex. Microwaves, radio waves, UV waves The Earth is located in the Goldilocks Zone, not too hot, not too cold, just right!
5 SUNSPOTS dark patches of slightly cooler (3500 C) surface areas on the sun, they increase and decrease in number on an 11-yr cycle. They may be related to changes in the Earth s climate. SOLAR FLARES eruptions of gas on the suns surface can last a few hours, temperatures increase up to 11,000,000 C Creates Solar Winds
6 Solar Wind page 393 Hot E bubbles pop on the surface of the sun and send high E particles rushing past Earth. Earth is protected from this solar wind by its magnetic field. Some of the particles enter the Earth s atmosphere at the poles where they collide with the gas in the atmosphere to create Auroras (Northern/Southern lights) page 394.
7 Some solar winds can disturb Earth s magnetic field and disable satellites, knock out power lines, and expose astronauts to high levels of radiation
8 Section 11.2 page 398 Characteristics of the Celestial Bodies of the Solar System
9 The Planets To be a planet you must orbit 1 or more stars be large enough so its gravity holds it in place be the only body in its orbital path
10 Astronomical Units (AU) Used to measure distances in space 1 AU = 150 million km (the distance from the Earth to the Sun) 5.27 AU 1 AU
11 Activity 11-2A: Terrestrial and Jovian Planets Listen to the information contained in the video on the planets and complete the table on page 402! Mnemonic Device to Remember the order of the Planets??? Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune
12 PLUTO Now considered Dwarf Planet a celestial body orbiting the Sun that is generally smaller than a planet but massive enough for its own gravity to give it a round shape. However they are not strong enough to clear their orbit of debris There are many other dwarf planets some are bigger and some like Pluto have moons
13 A Comparison of 3 dwarf planets and Earth, notice some have moons and some don t
14 COMETS dirty snowballs composed of ice, rock and gas Originate from the Kuiper Belt and Oort Cloud They travel in long elliptical orbits around the sun which are affected by the gravitational pulls of other planets It has a long dust tail as sunlight starts to melt the ice, these can stretch millions of km Most famous Halley s comet which is visable every 76 years or so
15 Periodicity of Comets: "Period" is the amount of time it takes an object in orbit to return to its starting location. Comets travel in short and long periods around the sun in elliptical orbits
16 The elliptical orbit of Halley s Comet
17 ASTEROIDS Small bodies believed to be the leftover remains of the formation of the Solar System Mostly found in an asteroid belt between Mars and Jupiter They have irregular shapes Range in size from a grain of sand up to 1000km An asteroid up to 1 km would devastate Earth
18 METEORS Meteoroid a rocky chunk, broken off an asteroid or planet, which floats through space Meteor a meteoroid that burns up as it passes through Earths atmosphere, seen as a shooting star Meteorite a meteoroid that does not burn up fully in the Earths atmosphere and hits the Earths surface
19 Deep Impact Sites A place where a relatively small object (meteorite) has collided with a larger object (planet) Produces a fairly circular depression in the surface of the larger object referred to as an impact crater