Science Form 2 - Chapter 13

Science Form 2 - Chapter 13

Meteoroid, Asteroid, Comet

Meteoroid

• Small pieces of stones and metals that float and move in space.

• Size : 

   $10\ \mu m-1\ m$ 

• Originates from fragments of asteroids and comets.

• Temperature of its surface in outer space is 0 $\degree C$  .

• The meteoroid moves at varying speeds.

Asteroid

• Big rocks and metals that move around the Sun in their own orbits

• Size : 1m to 1000 km

• Made up of stones and metals such as iron and nickel.

• The temperature on its surface is around -73°C.

• Travels around the Sun at an average speed of 25 km s^-1.

• Originates from the asteroid belt which is located between Mars and Jupiter.

Comet

• A small body made up of a mixture of ice, gas and dust and circles the Sun in its own orbit.

• Has two parts, head and tail.

• Tail : 150 000 000 km

• Head : 250 000 km

• Made up of gas and water that freeze into ice, dust and rocks.

• Moves around the Sun in its own elliptical orbit.

• Its average speed ranges from 10 km s^-1 to 70 km s^-1.

Multiple Choice

Small pieces of stones and metals that float and move in space.

• Meteorite

• Meteoroid

• Asteroid

• Comet

Multiple Choice

Big rocks and metals that move around the Sun in their own orbits

• Meteorite

• Meteoroid

• Asteroid

• Comet

Multiple Choice

Small body made up of a mixture of ice, gas and dust and circles the Sun in its own orbit.

• Meteorite

• Meteoroid

• Asteroid

• Comet

When a meteoroid enters the Earth's atmosphere, it is known as meteor.

When meteor reaches the Earth, it is called meteorites.

Crater form by meteorite

Movement of Asteroids

• Asteroid moves within the asteroid belt.

• There are also asteroids outside the asteroid belt for example Apollo, Amor and Aten

• A collision between the Earth's orbit and the asteroid's orbit can happen at the intersection point or on the paths close to both orbits.

• A collision between huge asteroid and Earth can cause destruction to the living things on Earth.

Movement of Comets

• Most comets originate from Kuiper belt and Oort cloud.

• When the comet gets closer to the Sun, the speed of comet increases, the ice on the head of comet turns into gas and forms the long tail.

• The tail of the comet would always be further from the Sun because of the blowing solar winds.

• Comets easily slip out of their orbits due to the strong gravitational pull from outside planets.

• The comets that slip out are at the risk of colliding with the Earth at high speed.

Multiple Choice

Which of the following is not in outer space?

• Meteorite

• Meteoroid

• Asteroid

• Comet

Multiple Select

These asteroid moves outside the asteroid belt.

• Apollo

• Aten

• Amor

• Ceres

Multiple Select

Most of the comets originate from the

• Asteroid belt

• Kuiper belt

• Oort cloud

• Jupiter

Multiple Choice

Comets easily slip out their orbits due to the strong gravitational pull from outside planets.

• True

• False