This document discusses comets, asteroids, and meteoroids. Comets are icy bodies that originate from the Oort cloud or Kuiper belt, while asteroids are rocky fragments left over from the formation of the solar system. As comets approach the sun, their ice evaporates, forming a coma and tail. Asteroids orbit mainly between Mars and Jupiter. Meteoroids are small particles that can burn up in the atmosphere as meteors, or survive impact as meteorites.

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Comets,
Asteroids and
Meteoroids

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In this lesson, you will understand the characteristics of
comets, meteors and asteroids.

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ASTEROIDS
METEOROIDS
METEORS
METEORITE
COMETS

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 Comets, meteors, and asteroids come in
different sizes and compositions. A
relatively higher amount of silicate
content caused these celestial bodies
to reflect light
Silicates are minerals which contain the
elements silicon, oxygen and at least one
metal which is responsible for comets and
asteroids to be able to reflect light.
Comets, Asteroids and Meteoroids

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Comets and asteroids are referred to by
astronomers as Near-Earth Objects
(NEO).
 Comets are icy bodies or objects while
asteroids are rocky fragments.
 Comets and asteroids are the remnants
from the formation of the solar system
4.6 billion years ago.
Comets, Asteroids and Meteoroids

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Comets, Asteroids and Meteoroids
Both the comet and asteroid orbit the
Earth and move relatively slow when
viewed from the Earth. This means that
you can view a comet for up to a year
in the night sky.
The main difference between
the comet and asteroid is the
origin. Comets typically come
from the Oort Cloud which is
beyond the solar system and
some from the Kuiper Belt
which is beyond the Neptune’s
orbit. Long-period comets
originate from the Oort Cloud
while a short-period comes
from the Kuiper Belt.

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COMPOSITION OF COMETS: Ice, dust, and small rocky
particles
PARTS/VOCABULARY FOR COMETS
A. Core
 Nucleus- solid inner core, made of frozen water
 Coma- cloud of dust and gas
 Tail- gas and dust can be seen as the sun heats
the comet & blows it away from the sun
Comets, Asteroids and Meteoroids
The “dirty snowball” made of
ice is the nucleus of a
comet. As the comet gets
closer to the Sun, the ice
melts and evaporates together
with dust particles. These
particles of gases make a
shining “head” around the
comet called a coma.

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the most famous comet of the
20th century. Only known as the short-period
comet. It takes 75- 79 years for Comet Haley to
orbit the Sun..
We can view it in the sky every
time it comes closer to the Sun.
All other comets have been
identified as long-period comets
since it takes 200 to several
thousand years to complete their
orbit around the Sun.

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Most asteroids, on the other hand,
originate from the Main Asteroid Belt
between Mars and Jupiter.
This belt is theorized by
scientists as remnants of a
planet that did not
completely form.
The orbit of an asteroid
is more rounded and less
elliptical than the orbit
of a comet.

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• In February 2013, Asteroid 2012 DA14
made a very close approach to Earth
as it orbited the Sun.
• In December 2012, during the midst of
the doomsday prophecies, Asteroid
Toutatis also made a near approach to
Earth but not as close as Asteroid
2012 DA14.

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meteoroid is a small rock or particle debris in the
solar system. Ranging in size from dust to around 10
meters in diameters.
 Meteoroids often enter the Earth’s
atmosphere.
 A meteoroid that burns up as it passes
through the Earth’s atmosphere is known
as a meteor (shooting star).
 A meteoroid that survives falling through
the Earth atmosphere and colliding with
the Earth surface is known as a meteorite
 When many meteors occur in a close time
frame in the same part of the sky it is
called a meteor shower

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ACTIVITY: MATCH IT!
Directions: Match Column A with Column B.

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