Asteroids are rocky objects that orbit the sun between Mars and Jupiter. They range in size from Ceres, which is about 1000 km in diameter, to pebbles. Most asteroids inhabit the asteroid belt between Mars and Jupiter, where they are thought to have formed from the leftover debris from planet formation. Some asteroids cross into Earth's orbit and are called Near-Earth Asteroids. Asteroids can be categorized by size, composition, and orbital location. They pose a threat to Earth if a large one were to impact, which could happen every 1000-10000 years on average. Asteroids differ from comets in that comets contain ice while asteroids are made of rock and metal. Meteoroids are smaller pieces of asteroids or

1. ASTRONOMY:
ASTERIODS

2. — PLATO, PHILOSOPHER
"Astronomy compels the soul
to look upwards, and leads us
from this world to another."

3. INTRODUCTION
Asteroids are rocky and metallic objects that
orbit the Sun but are too small to be
considered planets. They are known as minor
planets. Asteroids range in size from Ceres,
which has a diameter of about 1000 km, down
to the size of pebbles. Sixteen asteroids have
a diameter of 240 km or greater.

4. Size of an
asteriod
01
TABLE OF CONTENTS
The Asteriods
Belt
02
Near-Earth
Asteriods
(NEAs)
03
Classification
of Asteriods
04

5. Fact!
An asteroid is an irregular shaped rocky object
in space (like a space potato). It may be the
shattered remains of objects left over from
the time when the planets were formed.

6. Size of an
asteriod
01

7. How big are asteroids?
Larger than meteoroids.
Asteroids range in size from Vesta – the largest
at about 329 miles (530 kilometers) in diameter –
to bodies that are less than 33 feet (10 meters)
across. The total mass of all the asteroids combined
is less than that of Earth's Moon.

8. The
Asteriod
Belt
02

9. The Asteriod Belt

10. Most are in a band that orbit the sun between
Mars and Jupiter (Asteriod Belt). Scientists
estimated that there are more than 750,000
asteroids (Asteriod belt)
Asteroid are called minor planets or planetoids.

11. Near-Earth
Asteriods (NEAs)
03

12. ● At least 1000 asteroid orbit outside of the
Asteriod Belt — these could be a danger to Earth.
● Asteriods that cross Earth’s orbit are called
Near-Earth Asteriods or NEAs.
● But if it did, the affect of the impact would
depend on the size of the asteroid.

13. 04
The Classification
of Asteriods

14. ● Ceres — (named after the Roman goddess of
agriculture and as the protecting goddess in Sicily).
It is the largest asteroids with a diameter of 940
km.
● Pallas — Second to the largest, with a diameter of
540 km.
● Vesta — with a diameter of 510 km.
According to their size:

16. ● Ida — about 36 miles wide.
● 1991 BA — is one of the smallest
measuring only 20 feet across.
Other asteroids that range from 50 to
100 diameter

17. ● C-type asteroids or carbonaceous
asteroids — are greyish in color and the
most common; 75% of the asteroids fall in
this category and they inhabit the main
belt.
According to their color and composition:

19. ● S-type asteroids or silicaceous asteriods — are
made up of iron and magnesium silicate making them
greenish to reddish in color. 17% of this type
dominating the inner asteroid belt.
● M-type asteroids or metallic asteroids — are rich
in metallic substances such as nickel-iron, giving
them reddish in color. Inhabit the middle region of
the main belt.

20. ●Athens — lie outside the asteroid belt, near the
orbit of Mars including Ceres, Pallas, Juno and Vesta.
●Apollos — lie near Earth, which sometimes crosses
Earth’s orbit including;
Icarus (reached the Earth at about 6 million km.)
Geographos (reached Earth about 9 km.
Eros (reached Earth about 485,000 miles.
According to their position:

21. ● Trojan — known to dwell along Jupiter’s
orbital path and lie within the asteroid
belt.

22. FAQS about
Asteriods?

23. How do
asteroids form?

24. ● 4.6 billion years ago, asteroids are leftovers from
the formation of our solar system.
● The birth of Jupiter prevented any planetary bodies
from forming in the gap between Mars and Jupiter,
causing the small objects that were there to collide
with each other and fragment into the asteroids.

25. How are
asteroids found?

26. ● Italian priest and astronomer Giuseppe Piazzi
accidentally discovered the first and largest
asteroid, Ceres, orbiting between Mars and Jupiter
in 1801.
● Prog Catalina Sky Survey in Arizona and the Pan-
STARRS telescopes in Hawaii have each discovered
thousands of asteroids.
How are asteriods found?

27. Do asteroids
hit earth?

28. ● 4.5 billion years ago, asteroids and comets
have routinely slammed into the planet. The
most dangerous of the asteroids that hit
Earth are extremely rare.
● Asteroids capable of global disaster would
have to be more than a quarter-mile wide.
Do asteriods hit earth?

29. ● Such an impact would raise enough dust into the
atmosphere to effectively create a "nuclear winter,"
severely disrupting agriculture around the world.
● Asteroids that large strike Earth only once every
1,000 centuries on average..
Do asteriods hit earth?

30. ● Smaller asteroids that are believed to strike Earth
every 1,000 to 10,000 years could destroy a city or
cause devastating tsunamis.
● Space rocks smaller than 82 feet (25 m) will most
likely burn up as they enter Earth's atmosphere.
Do asteriods hit earth?

31. What is the difference
between asteriods and
comets and meteors?

32. Asteroids are made up of metals and rocky material, while
comets are made up of ice, dust and rocky material. Both
asteroids and comets were formed early in the history of the
solar system about 4.5 billion years ago.
Asteroids formed much closer to the Sun, where it was too
warm for ices to remain solid. Comets formed farther from
the Sun where ices would not melt. Comets which approach
the Sun lose material with each orbit because some of their
ice melts and vaporizes to form a tail.
Asteriods vs. Comets vs. Meteors

33. An asteroid is a small, rocky object and when seen in a telescope, it
appears as a point of light. Most asteroids are found in a ring between
the orbit of Mars and Jupiter called the asteroid belt.
Some asteroids are round, some are elongated, and some even have a
satellite. A comet also orbits the Sun, but unlike an asteroid, it's
composed of ice and dust. So, when a comet gets close to the Sun, its ice
and dust content start to vaporize. So, when seen in a teleA meteoroid is
a small piece of asteroid or a comet, typically pebble-sized, but could be
a little smaller or a little larger, and often created from a collision.
Asteriods vs. Comets vs. Meteors

34. When a meteoroid gets close to the Earth and enters the
Earth's atmosphere, it's called a meteor. And a meteor
enters the Earth's atmosphere at a very high speed. So
it burns up and produces a streak of light called a
shooting star. So, if you have seen a shooting star, you
likely saw a meteor. And if a meteor survives the burn
and lands on the ground, it's called a meteorite.
Asteriods vs. Comets vs. Meteors

35. OUR GROUP (3)
LABE, CINDY
PATINGA,
CHRISTIAN
LENDIO,
ROSELYN
TANILON, EDGEN
MAR
QUINOL, VANESSA

36. THANKS!