Planets

Question 1

What properties does a celestial object need to be considered a planet?

Answer 1

1. They orbit around the sun
2. They are spherical due to gravity
3. Dominate their orbit
4. Are either “terrestrial” or “gas giants”

Question 2

Why are planets spherical and some asteroids aren’t?

Answer 2

The larger an object is, the bigger the gravitational pull. This way, large objects are forced by gravity to become circular.

Question 3

Dwarf planets are (4)

What are they made of? (2)

Where do they originate? (2)

Answer 3

• are spherical
• orbit the sun
• but they don’t DOMINATE their orbit
• are always smaller than planets.
• can be made of ice and dust
• or metal and rock
• originate beyond Neptune’s orbit
• but some are in the asteroid belt

Question 4

Comets

Made of? (1)
Orbit is? (1)
originate? (1)

Answer 4

• ice and dust
• elliptical
• beyond neptune’s orbit

Question 5

What type of comets reside in the Kuiper Belt?

The Oort Cloud?

Answer 5

KB: Short period comets who’s full orbit is >200 years

OC: long period comets who’s orbit is >200 years

Question 6

When will a comet have a tail?

Answer 6

When it is near the sun and the ice begins to melt

Question 7

Asteroids

Orbit how and where? (2)
Made of (2)
Usual Appearance (2)

Answer 7

• elliptical orbit
• orbit the sun between Mars and Jupiter ( the asteroid belt)
• metal and rock
• small and irregularly shaped

-some asteroids are large enough to be considered dwarf planets

Question 8

Meteoroids vs Asteroids

• which is bigger?
• what are they made of?

Answer 8

• meteoroids are much smaller than asteroids, but are made of the same materials. ( metal and rock )

Question 9

The parts of our solar system are ?

Answer 9

The sun, the eight planets + their moons, and billions of other celestial objects.

Question 10

What really are shooting stars?

Answer 10

They are comets that have entered earth’s atmosphere and started to burn. This is why they have a tail.

Question 11

Solid remains of a meteor/meteoroid that did not completely burn up before hitting the surface of the earth are called?

Answer 11

Meteorites

Question 12

What meteor impact created the Canadian Shield? When?

Answer 12

1.8 billion years ago in Sudbury Ontario

Question 13

What meteor contributed to the extinction of the dinosaurs? When?

Answer 13

65 million years ago in Chicxulub Mexico

Question 14

What meteor impact levelled trees, broke windows, and caused a brilliant blue light without any actual impact? When?

Answer 14

1908, Tunguska Siberia

Question 15

What meteor impact is supposedly the biggest space rock ever to hit the earth with a magnetic field of over 500 kilometres wide? When?

Answer 15

250 million years ago, Antarctica

Question 16

What small meteor impact created a crater about 1 kilometre wide? When?

Answer 16

Arizona USA, between 20 000 and 50 000 years ago

Question 17

Which planets have atmospheres? What are they like?

Answer 17

Venus- very dense
Earth- moderate o2, water vapour and nitrogen
Mars- very thin
Jupiter, Saturn, Uranus, Neptune- hydrogen, methane, helium

MERCURY HAS NO ATMOSPHERE

Question 18

Define heliopause

Answer 18

When the sun’s gases collide with stellar wind