P2 - Solar System & Asteroids and Comets

Question 1

What is required for something to change direction?

Answer 1

Things only change direction when a force acts on them, if there was no force acting on them, they would move in a straight line or stay still.

Question 2

What force acts on planets?

Answer 2

Gravity, (Gravitational Attraction) acts on planets in the solar system, the solar system is essentially held together by gravitational attraction.

Question 3

How does gravity work?

Answer 3

Gravity pulls everything in the universe towards everything else, when referring to planets the gravitational pull is very large, they keep planets, satellites, moons etc.. in their orbits; the pull of gravity gets smaller the further away you go from an object, this is why you are pulled strongly towards the Earth and don’t go hurtling into the sun.

Question 4

What is circular motion caused by?

Answer 4

Circular motion is always caused by a force towards the center of the circle, for planets,moons etc.. in an orbit this force is provided by gravity

Question 5

What is a centripetal force?

Answer 5

A force that causes a circular motion is called a centripetal force.

Question 6

Where in this solar system is a belt of asteroids?

Answer 6

There’s a belt of asteroids orbiting between Mars and Jupiter

Question 7

Why is there an asteroid belt between Jupiter and Mars?

Answer 7

When the solar system was forming the rocks between mars and Jupiter didn’t form a planet, the large gravitational attraction of Jupiter kept interfering.

• This left millions of asteroids, measuring up to about 100 km in diameter, they orbit the sun between the orbits of Jupiter and Mars.
• Asteroids usually stay within their orbit, but sometimes they’re pushed or pulled into a different one.

Question 8

What are asteroids?

Answer 8

Asteroids are piles of rubble and rock in space.

Question 9

What are meteors?

Answer 9

Meteors are rocks or dust that enter the Earth’s atmosphere.

Question 10

What happens when meteors pass through the atmosphere?

Answer 10

Meteors burn up as they pass through atmosphere, we would see them as “shooting stars”.

Question 11

What is a meteorite?

Answer 11

A meteorite is a part of the meteor that did not burn up that crashes into the Earth’s surface., however this happens rarely.

Question 12

What can meteorites and meteors do to the Earth?

Answer 12

Meteors and meteorites can start fires, and throw lots of hot rocks and dust into the air, they can also make big holes in the ground called craters.

Question 13

What can the dust and smoke from a large meteorite/meteor do?

Answer 13

The dust and smoke from a large impact can block out the sunlight for many months, resulting in climate change which in turn can cause species to become extinct.
For example 65 million years ago an asteroid about 10 km across struck the Yucatán peninsula in Mexico, the dust it kicked up caused global temperature to plummet and over half the species on Earth subsequently died out, possibly including the last dinosaurs.

Question 14

What evidence is there to suggest that asteroids have collided with Earth in the past?

Answer 14

There are big craters

• Layers of unusual elements in rocks, these must have been brought by an asteroid
• Sudden changes in fossil numbers between adjacent layers of rock as species suffer extinction.

Question 15

What kind of orbit do comets take around the sun?

Answer 15

Comets orbit the sun in very Elliptical Orbits

Question 16

What are comets?

Answer 16

Comets are balls of rock, dust and ice, which orbit the sun in very elongated ellipses often in different planes from the planets.

Question 17

Where do Comets come from?

Answer 17

Comets come from objects orbiting the sun way beyond the planets.

Question 18

What happens to the Comet as it approaches the sun?

Answer 18

As the comet approaches the sun its ice melts leaving a bright tail of gas and debris, which can be millions of kilometers long, this is what we see from Earth.
The comet will speed up as they approach the sun, because the sun’s gravitational pull increases as you get closer.