160 likes | 278 Vues
Today is Tuesday, June 4 th , 2013. Homework: Complete rockets (launch is THIS FRIDAY!!!!) Understand how Newton’s Third Law of Motion makes YOUR particular rocket work! Warm UP: With your shoulder partner, discuss what you think the difference between a comet, asteroid, and meteoroid is.
E N D
Today is Tuesday, June 4th, 2013 Homework: • Complete rockets (launch is THIS FRIDAY!!!!) • Understand how Newton’s Third Law of Motion makes YOUR particular rocket work! Warm UP: With your shoulder partner, discuss what you think the difference between a comet, asteroid, and meteoroid is.
Goal for Today • SWBAT demonstrate the ability to differentiate between solar bodies by identifying and seeing the characteristics of comets, asteroids and meteoroids.
Only write down the BLUE text… Date: Tuesday, June 4th, 2013 Title: Other Solar System Bodies
Comet • Frozen mass of different types of ice and dust orbiting the Sun • Gas and dust reflect sunlight, which is why they glow • Tail always points AWAY FROM the Sun Haley’s Comet, seen every 76 years as it nears the sun….last seen in 1986 and your science teacher saw it then (but doesn’t remember because he was ___ years old!!!!!)
Artist’s Depiction of a Comet Dust tail – fine dust particles that escape the nucleus as the ice melts; wide and yellowish Ion tail – made up of various glowing charged gases; narrow and bluish • Nucleus – center, made of dust and ice (frozen water and frozen gases); “dirty snowball”; main portion of comet – with it all the time!!!! Coma – giant cloud of dust and evaporated gases surrounding the nucleus
Dust Ion Two tails of Comet West, 1976 Comet Hale-Bopp, 1997, your science teacher saw this one and he remembers it!!!! How old was Mr. Gross when it last passed by??? Comet McNaught, 2007
Asteroid Eros (33 km long) Asteroids • Rocky mass up to several hundred kilometers wide that revolves around the Sun • Size ranges from the 6 m Asteroid 1991 BA to the 933 km Asteroid Ceres (is spherical and technically considered a “dwarf planet”, but found in Asteroid Belt)
Most asteroids are contained in the Asteroid Belt, which is between Mars and Jupiter.
Many scientists believe that an asteroid collided with Earth 65 million years ago, causing huge climate changes and the extinction of dinosaurs (called “K-T Extinction Event”) • Site of impact was at the Chicxulub (CHEEK-shoo-loob) Basin, which is now buried under sediment
Tunguska EventTunguska River, Russia • Happened in Siberia in 1908 • Biggest modern day impact either by an asteroid or comet • Blast released 15 megatons of energy – about a thousand times of an atomic bomb. Even lit up the sky in London. 3D rending of Lake Cheko (level of the lake has been lowered 40 m to better show the shape of the lake). Possible final site of impact, which is 8 km from epicenter. Trees lay strewn across the Siberian countryside in 1953, 45 years after the mysterious aerial explosion.
Meteoroid • A small asteroid • Most are the size of pebbles or grains of sand Meteor – A piece of meteoroid enters the Earth’s atmosphere, causing a bright streak of light across the sky as it burns up entering Earth’s atmosphere due to friction at such high speeds Meteorite – The portion of a meteor that doesn’t burn up in the atmosphere and actually hits Earth’s surface. This is the Willamette meteorite (1902), largest single meteorite found in the US.
Hoba Meteorite, largest single meteorite in the world in Namibia. Thought to have landed 80,000 years ago.
Barringer Meteorite CraterWinslow, Arizona, USA • Formed 49,000 years ago by a 300,000 ton meteorite.
Closing it up…. • What do some scientists think caused the extinction of the dinosaurs? • A meteorite which crashed into the Chicxulub Basin. • What is the difference between a meteor and a meteorite? • A meteor burns up entering the Earth’s atmosphere and a meteorite actually hits Earth’s surface • Which direction does a comet’s tail face? • Away from the Sun