Transcript Warm-Up
Order of the Planets from the Sun • Acronym- My Very Educated Mother Just Served Us Nachos. • Planets- Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune Requirements to be Called a Planet! 1. Round 2. Revolve around the sun 3. Orbit the sun in the same plane/position as the other planets. Mercury • The closest planet to the sun • Has the shortest revolution- 88 days • The smallest planet • No moon Venus • The hottest planet because it is so close to the sun and has a thick atmosphere to hold in energy- greenhouse effect • Visited by the Russian probe Venera • Covered in Volcanoes Earth • The living planet; the only planet we know that has life Mars • Most similar to earth (in diameter, mass, rotation and revolution, temperature) • Has 2 moons • Has some water in the frozen ice caps at its north and south poles What separates Inner planets (Terrestrial) from the outer planets (Jovian) • Asteroid belt just beyond Mars, separates inner planets from outer planets. Jupiter • The largest planet • Has at least 17 moons and 4 rings • Has the Great Red Spot: A calm area surrounded by a stormy atmosphere • Europa may have ocean beneath ice surface. Saturn • The least dense planet- could float on water because it is less dense than water • 24 moons • Rings made of chunks of ice • Has a huge system of rings around it made of billions of chunks of ice & rock Uranus • Obits the sun on its side • 20 moons • Appears turquoise due to methane gas Neptune • The farthest planet from the sun • • • • The coldest planet Has 8 moons and 4 rings Has the longest revolution Has Great Dark Spot (a massive storm)has vanished. Planet Mini-Quiz! 1. Which planet is the most similar to earth? 2. Which planet is made mostly of methane gas? 3. Which planet can float on water? 4. Which planet is the hottest and why? Solar System Debris Comets & TNOs • Comets- Dust particles in a mixture of H2O, CO2, Methane, & Ammonia. “dirty snowballs” • Comets found in Edgeworth-Kuiper Belt beyond Neptune as solid body called nucleus. • When a comet travels in orbit close to sun (near Jupiter), it heats & solar wind forms a Coma (tail-gas & dust). Comets • Halley’s Comet has a orbital period of 76 years. • Last visible from Earth in 1986 Continued.. • TNOs- Trans Neptunian Objects. • Large bodies up to several hundred kilometers. • Located in the Edgeworth-Kuiper Belt. Asteroids • Solid, rock-like masses. • Irregular shape. • Believed to be leftover material from solar system formation. • Revolve around sun, most in circular orbit in asteroid belt. • Some have long elliptical orbits. Continued… • Perihelion- closest to sun • Theory: an asteroid or comet collided with Earth, causing dinosaur extinction 65 mya. • Scientists are currently researching ways to prevent collisions with Earth by diverting objects before they reach Earth. Asteroid pics Meteors & Meteoroids • Meteoroid- rock or icy fragment traveling in space. Range of sizes. • Meteor- light made by a meteoroid passing through Earth’s atmosphere. (shooting star) • Meteor Shower- when Earth passes through a comet’s tail & many particles from tail burn up in Earth’s atmosphere as meteors. Meteor shower Meteorites • The part of a meteoroid that survives to strike Earth’s surface. • • • • 3 Types: Stony (94%) iron (5%) stony-iron (1%) Impact Craters • Bowl-shaped depressions made by meteor/object that strikes a surface. • About 150 known impact craters on Earth • Arizona’s Barringer Meteor Crater. Assignment: Write down & answer the following questions on a separate sheet of paper. 1. What happens to comets as they approach the sun? 2. Where are most asteroids found? 3. Explain the difference between meteoroid, meteor, & meteorite. 4. Most meteorites formed between 4.55 & 4.65 b.y.a., making them a little older than the oldest moon rocks. Infer why moon rocks are younger than most meteorites.