1 Unit 2 Lesson 1 LESSON topic: formation of the solar system - Solar system formation - Star formation - Models of the solar system - Planets in our solar system
2 Big bang theory Origin of the universe According to this theory, all matter was created in an explosion approximately 13.7 billion years ago. The universe is STILL expanding to this day from the big bang. After millions of years, the gas and debris from the big bang began to cool and condense. This became the base for our universe.
3 Galaxies There are millions of galaxies in the universe. Inside the galaxies, millions of stars were also forming out of the same material.
4 Solar system development
5 Solar Systems Within each galaxy, there are millions of solar systems The Laplace hypothesis theory helps explain how our own solar system formed. Our solar system is 4.6 billion years old 1. large dust cloud is formed ( super nova) and begins to rotate 2. dust cloud condenses in center forms a star. 3. Dust clouds flattens into rings of debris 4. left over dust condenses as debris collides 5. Planets are formed
6 Astronomy facts The earth is the closest to the sun during the winter. And furthest away in the summer. The distance from the earth to the sun is called an astronomical unit. 1 AU is equal to 92,955, miles. The next CLOSEST star is 4.2 light years away NASA voyager space craft is traveling at 37- thousand mph. At that rate it couldn't reach the nearest star until after 80-thousand years.!!
7 All planets orbit the sun! like Earth s orbit, the other planets orbits are NOT perfectly circular, but in closed shapes called ellipses
8 Stars STARS A large ball of gas held together by gravity. Stars come in different colors- the color depend on its temperature Blue stars are Hotter, While red stars are cooler
9 STARS A large ball of gas held together by gravity. Luminosity = how bright a star is compared to our sun. Luminosity depends on size. The bigger the star, the more luminous. (brighter) *** NOTE- a star may appear brighter to us, because it closer, when in reality it may be a small, dimmer star. All Luminosity values are compared to the value of the sun ( which is see the HR Diagram)
10 ESRT pg 15
11 Our star the Sun
12 Our sun Our Sun is an average star (medium mass). It is approximately 5 billion years old. It will live for about another 5 billion years. It is composed mainly of hydrogen (which is the most abundant Or plentiful element in the universe).
13 How a star creates and uses energy that eventually makes its way to Earth The life cycle of a star is based on its MASS at birth (low or medium mass compared to a high mass star). A star is born when NUCLEAR FUSION takes place (hydrogen converting to helium). H + H He
14 Planets nets
15 Our solar system has 8 Planets Terrestrial (Inner) Planets: Mercury, Venus, Earth, Mars Rocky, high density, few moons (3) SOLAR SYSTEM DATA CHART PAGE 15
16 Inner Planets - Terrestrial
18 Asteroid belt Asteroid belt = clusters of asteroids orbiting the sun separating the terrestrial and Jovian planets Habitable Zone: where you may find life near a star
19 Gas Giants Jovian (Outer) Planets: Jupiter, Saturn, Uranus, Neptune Gas, low density, rings, many moons (154)
20 OuterOuter ( Jovian) planets Jovian Planets
22 Other celestial objects, Moons Asteroids Comets Meteoroids, Meteors Meteorites
24 Comparing and contrasting the planets using the ESRT page 15 Terrestrial ( inner) planets Size (DIAMETER) Distance # of moons DENSITY MASS Jovian ( outer) planets
25 Order of the Universe Smallest to Largest: Planet Star Solar System Galaxy Universe
28 Size Comparison of Celestial Objects: Fast Fact! Saturn will float in water due to its low density