Solar System - Science Olympiad Exam
Questions and Answers| Latest Update
2026
Exam
**Q1: How did the terrestrial planets form?**
**Answer:** In the proto-Solar-System, after the Sun formed,
materials orbiting close to it began to clump together. Lighter
materials like gases blew away, leaving only rocky material, which
formed the four terrestrial planets.
**Rationale:** The solar nebula theory explains that different
materials condensed at different distances from the Sun based on
temperature gradients.
---
**Q2: What are the characteristics of Terrestrial Planets?**
**Answer:** Solid bodies with a core surrounded by a mantle and
crust. Comprised mostly of heavier materials like rocks, stones, and
heavy metals (nickel and iron). They are smaller than gas giants and
very dense in comparison.
**Rationale:** Their proximity to the Sun meant lighter volatiles
were blown away by solar wind.
,---
**Q3: How old is the Solar System?**
**Answer:** 4.6 billion years
**Rationale:** Radiometric dating of meteorites provides this age.
---
**Q4: How did Mercury form?**
**Answer:** Mercury formed 4.55 billion years ago and is primarily
rocky. Rocks and metals very close to the Sun came together, but all
gases and atmosphere were blown away, leaving it small and rocky.
**Rationale:** Solar winds were strongest near the Sun, stripping
volatiles.
---
**Q5: How did Venus form?**
**Answer:** Venus formed from rocks and metals coming together.
However, solar winds are too weak to blow away Venus's
atmosphere, and heat has led to a greenhouse gas effect, making it
hotter than Mercury.
,**Rationale:** Venus's greater mass and distance allowed retention
of a thick CO₂ atmosphere.
---
**Q6: How did Earth form?**
**Answer:** Earth formed like other terrestrial planets. A large body
slammed into Earth, and material from that body and Earth formed
the Moon, explaining the Moon's relatively large size.
**Rationale:** The Giant Impact Hypothesis explains the Moon's
composition and angular momentum.
---
**Q7: How did Mars form?**
**Answer:** Mars formed similarly to Earth and possibly had large
oceans. For unknown reasons, these dried up, leading to Mars's
nickname as "The Red Planet."
**Rationale:** Iron oxide (rust) on the surface gives Mars its red
color.
---
, **Q8: How did the Moon form?**
**Answer:** A large body slammed into the young Earth, blowing
pieces into orbit. These pieces, along with Earth material, formed the
Moon.
**Rationale:** This explains the Moon's similar isotopic composition
to Earth's mantle.
---
**Q9: What are the surface features of Mercury?**
**Answer:** Mercury's surface is made of volcanic basalt and is very
smooth. It has no real atmosphere, allowing asteroids to impact,
though stopped by its thick mantle. It has a dark, cratered
appearance.
**Rationale:** Lack of atmosphere means no weathering, preserving
impact craters.
---
**Q10: What are the surface features of Venus?**
**Answer:** Venus has a thick atmosphere of sulfuric acid clouds. Its
surface features include volcanoes (Maat Mons), mountains, valleys,
lava channels, pancake domes, and impact craters.
Questions and Answers| Latest Update
2026
Exam
**Q1: How did the terrestrial planets form?**
**Answer:** In the proto-Solar-System, after the Sun formed,
materials orbiting close to it began to clump together. Lighter
materials like gases blew away, leaving only rocky material, which
formed the four terrestrial planets.
**Rationale:** The solar nebula theory explains that different
materials condensed at different distances from the Sun based on
temperature gradients.
---
**Q2: What are the characteristics of Terrestrial Planets?**
**Answer:** Solid bodies with a core surrounded by a mantle and
crust. Comprised mostly of heavier materials like rocks, stones, and
heavy metals (nickel and iron). They are smaller than gas giants and
very dense in comparison.
**Rationale:** Their proximity to the Sun meant lighter volatiles
were blown away by solar wind.
,---
**Q3: How old is the Solar System?**
**Answer:** 4.6 billion years
**Rationale:** Radiometric dating of meteorites provides this age.
---
**Q4: How did Mercury form?**
**Answer:** Mercury formed 4.55 billion years ago and is primarily
rocky. Rocks and metals very close to the Sun came together, but all
gases and atmosphere were blown away, leaving it small and rocky.
**Rationale:** Solar winds were strongest near the Sun, stripping
volatiles.
---
**Q5: How did Venus form?**
**Answer:** Venus formed from rocks and metals coming together.
However, solar winds are too weak to blow away Venus's
atmosphere, and heat has led to a greenhouse gas effect, making it
hotter than Mercury.
,**Rationale:** Venus's greater mass and distance allowed retention
of a thick CO₂ atmosphere.
---
**Q6: How did Earth form?**
**Answer:** Earth formed like other terrestrial planets. A large body
slammed into Earth, and material from that body and Earth formed
the Moon, explaining the Moon's relatively large size.
**Rationale:** The Giant Impact Hypothesis explains the Moon's
composition and angular momentum.
---
**Q7: How did Mars form?**
**Answer:** Mars formed similarly to Earth and possibly had large
oceans. For unknown reasons, these dried up, leading to Mars's
nickname as "The Red Planet."
**Rationale:** Iron oxide (rust) on the surface gives Mars its red
color.
---
, **Q8: How did the Moon form?**
**Answer:** A large body slammed into the young Earth, blowing
pieces into orbit. These pieces, along with Earth material, formed the
Moon.
**Rationale:** This explains the Moon's similar isotopic composition
to Earth's mantle.
---
**Q9: What are the surface features of Mercury?**
**Answer:** Mercury's surface is made of volcanic basalt and is very
smooth. It has no real atmosphere, allowing asteroids to impact,
though stopped by its thick mantle. It has a dark, cratered
appearance.
**Rationale:** Lack of atmosphere means no weathering, preserving
impact craters.
---
**Q10: What are the surface features of Venus?**
**Answer:** Venus has a thick atmosphere of sulfuric acid clouds. Its
surface features include volcanoes (Maat Mons), mountains, valleys,
lava channels, pancake domes, and impact craters.
