Topic 2.1 - Our Solar System

Question 1

How many known satellites, or moons, of planets are there in our solar system?

Answer 1

160 and this number keeps on growing

Question 2

Name all 5 dwarf planets in our solar system.

Answer 2

Ceres, Pluto, Haumea, Makemake and Eris

Question 3

What is an asteroid?

Answer 3

A small (mostly less than a few hundred km in size but larger than 10 m) solid bodies, with the majority orbiting in the Asteroid or Main Belt between the orbits of Mars and Jupiter

Question 4

What is the name of the brightest asteroid?

Answer 4

Vesta

Question 5

What is a comet?

Answer 5

Nuclei of ice, dust and rock that develop gaseous coma and tails when relatively close to the sun

Question 6

What is a centaur?

Answer 6

These show similarities to both asteroids and comets and are named after the mythological half-man, half-horse race of centaurs; they generally orbit the Sun between the orbits of Jupiter and Neptune and include Chiron, Hidalgo and Asbolus

Question 7

What are Trans-Neptunian Objects (TNOs)?

Answer 7

Objects orbiting the sun beyond Neptune

Question 8

Name 7 types of object that the sun is host to in our solar system?

Answer 8

1. 8 planets
2. Satellites of planets
3. Dwarf planets
4. Asteroids
5. Comets
6. Centaurs
7. TNOs

Question 9

What do the International Astronomical Union define a planet as?

Answer 9

A body that:
•Is in orbit around the sun
•Is large enough to be spherical
•Had ‘cleared its orbit’ of other objects

Question 10

What is the mean distance to the sun for each planet in our solar system in AU?

Answer 10

Mercury - 0.38
Venus - 0.72
Earth - 1
Mars - 1.5
Jupiter - 5.2
Saturn - 9.5
Uranus - 19.1
Neptune - 30

Question 11

What is the diameter of each planet in our solar system in km (rounded)?

Answer 11

Mercury - 4,800
Venus - 12,100
Earth - 12,800
Mars - 6,800
Jupiter - 143,000
Saturn - 121,000
Uranus - 51,000
Neptune - 50,000

Question 12

Name 4 facts about Mercury

Answer 12

1. Heavily cratered
2. Contains highlands
3. Lava-filled basins
4. Many parts of the surface appear to be almost identical to that of the moon

Question 13

Name 5 facts about Venus.

Answer 13

1. It’s backwards spinning
2. Similar to Earth in size
3. Clouds of sulphuric acid
4. Surface pressure 90 times greater than that on Earth
5. Dense atmosphere containing Carbon Dioxide which prevents infra-red radiation from leaving Venus making the surface and lower atmosphere so hot - a ‘runaway greenhouse effect’ with a temperature of 470℃

Question 14

Name 5 facts about Mars.

Answer 14

1. Has iron-rich rocks
2. Has seasonal ice caps
3. A 450 km-long water-carved canyon called Valles Marineris stretching east-west across its surface
4. Contains the highest volcano in the solar system - Olympus Mons
5. Has violent dust storms rage across its surface

Question 15

Name 3 facts about Jupiter.

Answer 15

1. Rotates on its axis in only 10 hours
2. ^Producing an equatorial bulge and causing dynamic wind that split the atmosphere into a series of red-brown belts and yellow-white zones
3. Jupiters Great Red Spot is an anticyclone system larger than Earth

Question 16

Name 4 facts about Uranus.

Answer 16

1. It spins almost on its side.
2. It’s almost featureless.
3. The blue-green colour is a result of the amount of methane in its mostly hydrogen and helium atmosphere.
4. 80% or more of its mass is made up of a fluid mix of water, methane and ammonia iced.

Question 17

Name 4 facts about Neptune

Answer 17

1. There is a great dark spot.
2. Has cirrus-like clouds of frozen methane at high altitudes.
3. It’s atmosphere also contains gigantic storms.
4. It also has a faint system of rings.

Question 18

Name the Galilean moons of Jupiter.

Answer 18

Io, Europa, Ganymede and Callisto

Question 19

Talk about Mars’ moons

Answer 19

Mars has two all moons Deimos (the smaller and more distant moon) and Phobos. Both are irregular in shape, only tens of km in size and heavily-cratered. Their densities are roughly half of that of Mars, and there composition is similar to that of typical asteroids. For these reasons most astronomers believe that Deimos and Phobos are captured bodies from the Asteroid Belt.

Question 20

Talk about Neptune’s moon Triton.

Answer 20

Triton is Neptune’s largest moon (only slightly smaller than our moon) and has a highly-inclined orbit and revolves around Neptune in the opposite sense to that in which Neptune spins. This suggests that Triton is a captured body, but because of its relatively large size and mass, astronomers believe that Triton’s collision might be as a result of a collision with Neptune or another of its moons.

Question 21

Which planets have ring systems?

Answer 21

All 4 gas giants- Jupiter, Saturn, Uranus and Neptune

Question 22

Describe ring systems.

Answer 22

Each ring system is divided into several distinct rings, each containing billions of individual particles of ice, rock and dust that range from a few micrometers to to several metres size

Question 23

What’s the difference between Saturn and Jupiters rings?

Answer 23

Jupiter has very dusty, dark rings whereas Saturn’s are icy and highly reflective

Question 24

How thick are ring systems?

Answer 24

1.5 km thick

Question 25

How wide are ring systems?

Answer 25

Up to hundreds of km wide

Question 26

Name the 2 inferior planets.

Answer 26

Mercury and Venus

Question 27

Name the 5 exterior planets.

Answer 27

Mars, Jupiter, Saturn, Uranus, Neptune

Question 28

Diagram of inferior planet at superior conjunction.

Answer 28

☀️=The Sun
🌍=The Earth
🌑=Inferior Planet

🌍 ☀️ 🌑

Question 29

Diagram of inferior planet at inferior conjunction.

Answer 29

☀️=The Sun
🌍=The Earth
🌑=Inferior Planet

 🌍        🌑     ☀️

Question 30

What is occultation?

Answer 30

When an inferior planet is close to superior conjunction, it may disappear for a short while behind the Sun; this event is known as occultation. Generally speaking, an astronomical body is occulted when it passes behind another and is temporarily hidden from view

Question 31

Diagram of superior planet at opposition.

Answer 31

☀️=The Sun
🌍=The Earth
🌕=Superior Planet

 🌕        🌍     ☀️

Question 32

Diagram of superior planet at conjunction.

Answer 32

☀️=The Sun
🌍=The Earth
🌕=Superior Planet

🌍 ☀️ 🌕

Question 33

Where do the planets appear to move through?

Answer 33

The zodiac band

Question 34

What’s the largest moon in our solar system?

Answer 34

Ganymede

Question 35

What is greatest elongation?

Answer 35

The angle between the Sun and a planet with Earth as its reference point - Mercury and Venus have 90 degree angle between Earth and Sun.

Question 36

What’s the best position to observe an inferior planet?

Answer 36

Greatest Elongation

Question 37

What’s transit?

Answer 37

When a smaller body passes in front of a larger body?

Question 38

When is the best time to observe a superior planet and why?

Answer 38

At opposition because they are closest to earth offering best resolution and full illuminated so visible through the night

Question 39

What are the problems of astronauts venturing further than the moon?

Answer 39

Space adaption syndrome
Psychological problems
Communication delays
Radiation risk

Question 40

What are the problems of astronauts venturing further than the moon?

Answer 40

Space adaption syndrome
Psychological problems
Communication delays
Radiation risk