origin-of-the-solar-system.pptx

ORIGIN OF THE SOLAR SYSTEM  Formation of the Solar System Any theory to describe the formation of our Solar System must be consistent with these facts: 1. Each planet is isolated in space. 2. The orbits are nearly circular. 3. The orbits of the planets all lie in roughly the same...

ORIGIN OF THE SOLAR SYSTEM  Formation of the Solar System Any theory to describe the formation of our Solar System must be consistent with these facts: 1. Each planet is isolated in space. 2. The orbits are nearly circular. 3. The orbits of the planets all lie in roughly the same plane 4. The direction the planets orbit around the Sun is the same as the Sun’s rotation on its axis. 5. The direction most planets orbit on their axes is the same as that for the Sun. 6. The direction of the planetary moon’s orbits is the same as that of the planet’s 2 rotation.  Nebular Theory for Solar System formation Our Sun and the planets began from a cloud of dust and gas (nebula) As the cloud contracts under its own gravity, the Sun is formed at the center. The cloud starts to spin and the smaller it contracts, the faster it of nservation spins. angular momentum ud forms a flattened, pancake shape. 3  Nebular theory Interstellar cloud of gas & dust collapsed under its own gravity Prediction: protoplanetary nebulae should be observed Explains all of the major features of solar system, and also the exceptions 4  Condensation Theory for Planet Formation The gas in the flattened nebula would never eventually clump together to form planets. Interstellar dust (grain-size particles) lies between stars These dust - remnants of old, dead grains stars. form condensation nuclei - other atoms attach to them to start the 5  What happened next….. Solar nebula contracts and flattens into a disk. Condensation nuclei form clumps that grow into moon- size planetesimals. Solar wind from star formation blows out the rest of the gas. Planetesimals collide and grow. Growing planetesimals form 6 OTHER THEORIES ABOUT THE FORMATION OF THE SOLAR SYSTEM ⋆VORTEX THEORY ⋆COLLISION THEORY 7  Any GOOD hypothesis about the origin of the solar system must explain most - if not all - of its characteristics:  All of the planets orbit the sun in the same direction, and in the same plane  The planets closest to the sun are small and rocky, have few moons  The planets further from the sun are large and contain more gas and icy materials  Most of the Moons orbit their planets in the same direction as the planets orbit the sun  Oldest meteorites are8 about 4.566 billion OUR SOLAR SYSTEM ⋆ Galaxies Our sun is 1 of trillions of stars in the universe. Stars are found in groups held together by gravity. ⋆ A huge group of stars is called a galaxy. ⋆ Our entire universe is made up of thousands of galaxies. ⋆ The images below show you how small we are compared to the entire universe. UNIVERSE GALAXY SOLAR SYSTEM The entire universe is made A huge group of stars A system of planets & stars that of thousands of galaxies held together by gravity. are found throughout galaxies  The Milky Way ⋆ Our Solar System is part of the “Milky Way” galaxy.  The Inner Planets (Terrestrial Planets)  Spinning Planets ⋆ Period of Rotation: amount of time that an object takes to rotate once. (1 Day) ⋆ Period of Revolution: time it takes an object to revolve around the sun once. (1 year) http://www.youtube.com/watch?v=97  Mercury ⋆ On Mercury you weigh only 38% of what you weigh on Earth. ⋆ Fastest orbiting planet ⋆ Planet nearest to the sun ⋆ One side of the planet can be 800 degrees Fahrenheit when the other can be -280 degree Fahrenheit at the same time. Cold on half of the planet and Hot on half facing the sun  Venus ⋆ On Venus you weigh only 91% of what you weigh on Earth. ⋆ Venus has 90 times the pressure of Earth ⋆ Venus has volcanoes like Earth ⋆ Rotates in the opposite direction of Earth. ⋆ One time there wre eoceans before they boiled away. ⋆ Second planet from the sun ⋆ Nicknamed “the evening star”  Earth ⋆ 23 hours and 56 min=1 Earth day (rotation) ⋆ 365 days =1 Earth year (revolution) ⋆ Earth is warm enough to keep most of its water from freezing and cold enough to keep it’s water from boiling ⋆ Temperature is between –13 degrees Celsius and 37 degrees Celsius ⋆ Third planet from the sun ⋆ Only planet with large amounts of liquid  Mars ⋆ Air Pressure on Mars is the same as 30 km above the Earth’s surface ⋆ Mars is in the form of ice. ⋆ Evidence that water was there at one time ⋆ Volcanic history like Earth. ⋆ It has the tallest mount of the planets (Olympus Mons) 3x’s size of Mt. Everest. ⋆ The RED Planet (Pink-Gold in color) ⋆ Has 2 Moons ⋆ Rocks and Sand  Outer Planets (Gas Planets or Jovial Planets)  Jupiter ⋆ Largest planet in the Solar System ⋆ Has a Great Red Spot from a storm system that is more than 400 years old (It is larger than Earth!) ⋆ 9 hours and 54 min=1 Jupiter day (shortest day) ⋆ Pressure is so great it would crush a spaceship. ⋆ Largest Planet ⋆ Giant ball of swirling gas  Saturn ⋆ 2nd Largest planet in the Solar System ⋆ 95 times more massive than earth. ⋆ Saturn has the largest rings of any planet, the rings are made of icy particles. ⋆ Most moons of any planet. 18 Moons ⋆ Has Rings that are made up  Uranus ⋆ Discovered in 1781 ⋆ Uranus appears blue-green in color ⋆ It’s axis of rotation is tilted 90 degrees ⋆ Moons are named after Shakespearean plays and formed from other broken moons. Has around 21 Moons  Neptune ⋆ Discovered in 1846 ⋆ Neptune has visual belts of clouds ⋆ Interior releases thermal energy to its outer layers. ⋆ Use to be the 8th planet after Pluto until 1999. o Fourth Largest Planet o Seven thin rings o 8 moons o Two dark spots  Pluto ⋆ Used to be considered a planet ⋆ One of Neptune’s moons ⋆ Gray in color  Terrerstrial vs. giant planets Giant (“jovian”) Terrestrial (“earth like”) 1. Lots of solids 1. Very little solid in the disk material in disk (cold > 5 AU) at 1 AU 2. Cores form 2. Form from rock from ice, rock and metal only and metal 3. Grow slowly 3. Grow large, (~100 million quickly (~1 years) million years)  Size Matters! Here is a diagram to show how the plants compare to each other, relative to their size! What about the SUN? o Is a star o Brings light o Brings warmth o Center of Solar System o Giant ball of gas What Keeps Our Planets & Other Objects In Space In Orbit?? GRAVITY & INERTIA  GRAVITY & INERTIA ⋆ Gravity – A force that pulls all objects toward each other. ⋆ Inertia – The tendency of an object to stay either at rest or in motion along a straight path So how does these 2 forces keep everything in orbit? Actual Orbit **Example: The picture to the right shows how inertia & gravity work  GRAVITY & INERTIA Actual Orbit If inertia was If gravity was Inertia & gravity work stronger than stronger than together to keep the gravity then inertia then moon orbiting the objects would objects would Earth. And they work stay on their together to keep planets crash straight path & orbiting the sun fly off into Other Space Objects COMETS ASTEROIDS METEOROIDS What is a comet? A comet is a small body made out of dust, rock, gas & ice. They are kind of like a dirty snowball Comets come from faraway regions of Comets are made up of different parts.  The nucleus  The coma What is an asteroid? Asteroids are large pieces of space rock with irregular shapes. They are also known as planetoids or  Most asteroids orbit the Sun in the asteroid belt located between Mars and Jupiter. A few asteroids approach the Sun more closely. Asteroids can collide with object such as Earth’s moon, creating huge craters on the surface. METEOROID Meteoroids are METEORS S & pieces of rock METEORITES or dust that are smaller than asteroids. Meteoroids are tiny particles left by an asteroid or a comet & most  enters Earth’s atmosphere, they usually burn up & make a fiery trail as it falls, it is then called a meteor or a “shooting star” Meteors that land on Earth are