Scholarship Astronomy

Question 1

What are the key facts about Mercury?

Answer 1

• Orbit: 88 Earth days
• Rotation: 59 Earth days
• 1 day (sunrise to sunrise): 176 Earth days
• Characteristics: Rocky, plains, many craters, no water
• Temperature: +465°C (towards the Sun), -184°C (facing away from the Sun)

Question 2

What are the key facts about Venus?

Answer 2

• Orbit: 225 Earth days
• Rotation: 243 Earth days (backwards)
• 1 day (sunrise to sunrise): 117 Earth days
• Atmosphere: Thick, 97% CO2, sulphuric acid clouds
• Temperature: Averages +460°C day and night
• High reflectivity makes it shine brightly in the sky

Question 3

What are the key facts about Earth?

Answer 3

• 70% surface covered in ocean
• Atmosphere: 21% O2, 50 km thick
• Average temperature: 15°C
• Water cycle & atmosphere cause constant erosion
• Carbon cycle regulates temperature
• Rock cycle recycles matter

Question 4

What are the key facts about the Moon?

Answer 4

• Large relative to Earth
  Orbit: 27.3 days (same side always faces Earth)
• Full Moon to Full Moon: 29.5 days
• No atmosphere or erosion
• Temperature: -250°C to +120°C
• Similar size to Sun from Earth -> solar eclipses
• Evidence of past liquid water

Question 5

What are the key facts about Mars?

Answer 5

• Distance: 1.52 AU from Sun
• Orbit: 687 Earth days
• Rotation: 24.5 hours
• 1 day (sunrise to sunrise): 24.5 hours
• Temperature: -133°C to +27°C
• 2 moons (probably captured asteroids)
• Tilted axis -> has seasons
• Thin atmosphere: 95.3% CO2, traces of N2, Ar, O2, H2O vapor, methane
  *Polar ice caps (dry ice + water ice)
• Olympus Mons: Largest volcano in Solar System
• Valles Marineris: Possible tectonic gash
• Possible evidence of liquid water in hydrated minerals

Question 6

What are the key facts about the Asteroid Belt?

Answer 6

• Location: Between Mars & Jupiter
• Mostly empty space with many asteroids
• Largest asteroids: Ceres (round), Pallas, Vesta
• Jupiter’s gravity may have prevented a planet from forming

Question 7

What are the key facts about Jupiter?

Answer 7

• Orbit: 11.9 Earth years
• Rotation & day: 9.8 hours
• Composition: 90% H, 10% He, small rocky core
• Winds: 500 km/h
• Great Red Spot: Giant storm
• Faint rings
• No spacecraft can land due to gaseous nature
• Io: Most volcanically active, tidal flexing causes magma
• Europa: Ice-covered, may have an ocean & geothermal activity

Question 8

What are the key facts about Saturn?

Answer 8

• Orbit: 29.5 Earth years
• Rotation & day: 10.2 hours
• 62 known moons
• Composition: H & He, rocky core, liquid hydrogen
• Winds: 1000 km/h
• Spectacular rings maintained by shepherd moons
• Enceladus: Ice surface, high albedo, plumes suggest ocean below
• Titan: Dense atmosphere, lakes of methane, cryovolcanoes

Question 9

What are the key facts about Uranus?

Answer 9

• Distance: 19 AU
• Orbit: 84 Earth years
• Rotation & day: 18 hours
• Composition: H, He, cool inner core
• Temperature: -224°C (cloud tops)
• 27 moons (largest: Miranda)
• Faint dark rings
• No spacecraft can land

Question 10

What are the key facts about Neptune?

Answer 10

• Orbit: 165 Earth years
• Rotation: 19 hours
• Densest gas giant: Gas, ice, rocky core
• Strongest winds in Solar System
• 13 moons (largest: Triton)
• Great Blue Spot: Massive hurricane
• Triton: Cold, nitrogen geysers, retrograde orbit (likely captured KBO)

Question 11

What are the key facts about the Kuiper Belt?

Answer 11

• Disk-shaped region beyond Neptune (30–100 AU)
• Contains small icy objects, remnants of Solar System formation
• Over 70,000 objects >100 km in diameter
• Pluto: Dwarf planet, KBO, 5 moons (Charon locked in orbit), icy-rocky

Question 12

What are the key facts about the Oort Cloud?

Answer 12

• Extended region beyond Kuiper Belt
• Contains icy remnants from Solar System formation

Question 13

What are the key facts about the Ecliptic?

Answer 13

• Sun’s apparent path across the sky
• Planets, Moon, and Sun move along the ecliptic

Question 14

What causes meteor showers?

Answer 14

• Occur when Earth crosses comet debris
• Example: Orionids from Halley’s Comet

Question 15

What are the key facts about comets?

Answer 15

• Origin: Kuiper Belt & Oort Cloud
• Short-period comets: From Kuiper Belt, <200 years (e.g., Halley’s Comet)
• Long-period comets: From Oort Cloud, >200 years, random orbits
• As comets approach Sun:
  
  • Ice sublimates, forms a glowing coma
  • Gas & dust tails extend away from Sun