Science 7 - Comets, Asteroids, and Meteors
one or more large asteroids hit the earth about ____ years ago
65 million
What is a meteoroid?
A chunk of rock or dust in space
What are comets?
A loose collection of ice, dust, and rocky particles whose orbits are very long narrow ellipses.
What is the Oort Cloud?
A spherical region that surrounds the solar system out to more than 1000 times the distance between Pluto and the sun
Where do most asteroids revolve?
Around the sun, between the orbits of Mars and Jupiter. (Asteroid belt)
what is the Kuiper belt?
Doughnut shaped region that extends from beyond Neptune's orbit to about 100 times Earth's distance from the sun
A doughnut-shaped region of comets that begins near Neptune's orbit is the ___
Kuiper belt
what are the two distant regions?
Kuiper belt and the Oort Cloud
A spherical region of comets is the __
Oort Cloud
A rocky object that revolves around the sun, but is too small to be considered a planet is a ___
asteroid
The region of the solar system between the orbits of Mars and Jupiter is known as the...
asteroid belt
how were the craters on the moon formed?
by meteoroids
clouds of gas and dust on a comet form a fuzzy outer layer called a __
coma
A chunk of ice and dust whose orbit is usually a long narrow ellipse is a...
comet
meteoroids come from...
comets or asteroids
smaller objects are...
comets, asteroids, meteoroids
nickname for a comet:
dirty snowball
4 parts of the comet:
head, nucleus, coma, tail
comet's head:
made from coma and nucleus
comet's coma:
made up primarily by gasses
scientists hypothesize that... (extinct dinos)
many species of organisms, including the Dinos, became extinct as a result of many asteroids hitting the earth
When a meteoroid enters Earth's atmosphere, friction causes it to burn up and produce a streak of light called a ___
meteor
If a meteoroid hits the Earth's surface, it is called a ____
meteorite
Meteoroids that pass through the atmosphere and hit earth surface are...
meteorites
A chunk of rock or dust in space that usually comes from a comet or an asteroid is called a ____
meteoroid
inner core of the comet is the...
nucleus
Most comets are found in...
one of two distant regions
when a meteor enters Earth's atmosphere, friction with the air creates heat and...
produces a streak of light that you can see in the sky-- a meteor
asteroids are too ___ to be considered planets
small and numerous
a comet's tail is _____ and can be more than __________
stretched very thinly/100 million kilometers long
clouds of gas and dust form a fuzzy outer layer called...
the coma
How does the tail of a comet form?
the comet heats up as it approaches the sun
