Transcript Comets, Meteors, and Asteroids

Bell work
 Have
scientists ever brought extraterrestrial
material to Earth? Scientists have studied
rocks from Mars and other parts of the solar
system. How have scientists obtained these
rocks?
 Record
your answer in your science
journal.
Comets, Meteors, and Asteroids
Today’s Objectives
Explain
why comets, asteroids, and meteoroids are
important to the study of the formation of the solar
system.
Describe
the similarities of and differences
between asteroids and meteoroids.
Explain
Earth.
how cosmic impacts may affect life on
Comets

Small body of ice, rock and dust loosely packed
together that orbits the sun
A comet is a “dirty snowball” about the size of an
earth mountain. (dirt and ice)
 Comets’ orbits are usually very long, narrow
ellipses.
 They produce tails of gas and dust when they
approach the sun.
 Look like “shooting stars” but can move much
slower.

Comet Parts
 Tails
 Ion-electrically
charged ions, always points
away from the sun
 Dust- follows the orbit of the comet
 Gas-follows the orbit of the comet also
 Can extend millions of km
Comet Parts
 Nucleus
 Averages
3 miles in diameter, by can be
between ½ and 100 km
 Solid, rocky, icy center
 Shows different features as it nears the
sun
 Coma forms a large halo around the
nucleus of a comet as it nears the sun
The
Coma’s halo is made of dust and gas
Structure of a Comet
Ion Tail
Dust
Tail
Coma
To Sun
Orbit
 Highly
elongated
 Very elliptical
Oort
Cloud
Oort cloudsphere that
surrounds the
solar system 1
light year away
from the sun
made of dust and
gas
The Oort Cloud
Kuiper Belt- outside orbit of Neptune- made of dust and rocks- where
most dwarf planets are found.
Comet names
 Comets
are often named after the person
who discovers them!
 Maybe the next one could be named after
you!
Comet Halley
Comet Halley 1910
•Pope Callixtus III
excommunicated
Halley's Comet in 1456
•In 1910, charlatans sold
"comet pills"
Orbit
Halley’s Comet (1986)
Halley’s Comet….
Orbits every 76 years
Hyakutake
Comet: Hale-Bopp
www.brainpop.com/science/space/comets/
 Winter and
early spring of
1997
 Next sighting:
4380
Hale-Bopp
Comet West
Today’s Objectives
Explain
why comets, asteroids, and meteoroids are
important to the study of the formation of the solar
system.
Describe
the similarities of and differences
between asteroids and meteoroids.
Explain
Earth.
how cosmic impacts may affect life on
Meteoroids, Meteorites, and Meteors
Meteoroid- small rocky body often made of rock,
metal, or dust.
 Meteorite- meteoroid that hits the Earth



Meteoroids survive as they pass through the atmosphere and hit Earth’s
surface
Meteor- meteoroid that burns up in the Earth’s
atmosphere


Shooting stars are not actually stars. These flashes of light across
the sky are small bits of rock burning up in the Earth’s
Atmosphere. They often move very fast across the sky.
They are called “fireballs” when it creates a long streak of light as
it gets close to the ground.
3 types
 Stony
 Metallic
 Stony-iron
The Cause of Meteor Showers
P55/Tempel-Tuttle
The 1833 storm
The 1966 storm
1997 Leonids from Orbit
Two Showers for Halley
Sporadic Meteors
Irons
Stony-Irons
Carbonaceous
Chondrite
Chondrites
Achondrite
Barringer’s Crater
An iron meteorite 100 feet across and 70,000 tons
slamed into the Earth at about 43,000mph in the
Arizona desert near Flagstaff 40,000 years ago.
Barringer Crater is 4,100 feet wide and 571 feet deep.
Other Impact Craters
SUMMARY
METEOROID: A piece of stone or metal
that travels in outer space.
METEOR: An object from space that
becomes glowing hot when it passes into
Earth's atmosphere.
METEORITE: A piece of stone or metal
from space that falls to Earth's surface.
Today’s Objectives
Explain
why comets, asteroids, and meteoroids are
important to the study of the formation of the solar
system.
Describe
the similarities of and differences
between asteroids and meteoroids.
Explain
Earth.
how cosmic impacts may affect life on
Asteroids

Small rocky bodies in orbit around the sun. (larger
than meteoroids)
Have the same compositional matter as the
Terrestrial planets
 Located between Mars and Jupiter in the Asteroid
Belt.
 Ceres was the largest asteroid ever discovered


Now it is classified as a Dwarf Planet!
Asteroids
Apollo
Trojans
Ida - Dactyl
Gaspra
Today’s Objectives
Explain
why comets, asteroids, and meteoroids are
important to the study of the formation of the solar
system.
Describe
the similarities of and differences
between asteroids and meteoroids.
Explain
Earth.
how cosmic impacts may affect life on