What is unusual about Triton's orbit?

It goes backward compared to Neptune's spin

It is perfectly circular around the Sun

What makes Triton unusual among large moons?

It is the only large moon with a retrograde orbit

How cold is Triton's surface?

Among the coldest measured in the Solar System

What will happen to Triton in the far future?

It will spiral in and break apart

Triton Quiz: Neptune's Backward-Orbiting Captured Moon

This Triton quiz visits Neptune's largest and strangest moon. Play 10 interactive questions on its backward, retrograde orbit, its likely capture from the Kuiper Belt, nitrogen geysers seen by Voyager 2, cantaloupe-like terrain, temperatures among the coldest measured, discovery by William Lassell in 1846 and its slow spiral toward Neptune.

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🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 150 Seconds

Question 1 / 10 Time: 150s

Planet
Which planet does Triton orbit?
Orbit
What is unusual about Triton's orbit?
Capture
What does the backward orbit suggest?
Unique
What makes Triton unusual among large moons?
Geysers
What did Voyager 2 see on Triton?
Terrain
What is some of Triton's terrain nicknamed?
Cold
How cold is Triton's surface?
Found
Who discovered Triton?
Year
When was Triton discovered?
Future
What will happen to Triton in the far future?

Explanations: answer key for all 10 questions

Q1: Which planet does Triton orbit?
Answer: Neptune
It is the planet's largest moon.
Q2: What is unusual about Triton's orbit?
Answer: It goes backward compared to Neptune's spin
This is a retrograde orbit.
Q3: What does the backward orbit suggest?
Answer: Triton was captured
It may have come from the Kuiper Belt.
Q4: What makes Triton unusual among large moons?
Answer: It is the only large moon with a retrograde orbit
Smaller moons sometimes orbit backward.
Q5: What did Voyager 2 see on Triton?
Answer: Nitrogen geysers
Dark streaks stain the surface.
Q6: What is some of Triton's terrain nicknamed?
Answer: Cantaloupe terrain
It looks like melon skin.
Q7: How cold is Triton's surface?
Answer: Among the coldest measured in the Solar System
Around minus 235 C.
Q8: Who discovered Triton?
Answer: William Lassell
It was just 17 days after Neptune.
Q9: When was Triton discovered?
Answer: 1846
Same year as Neptune.
Q10: What will happen to Triton in the far future?
Answer: It will spiral in and break apart
It may form a ring around Neptune.

The Moon That Orbits Backward

Triton is Neptune's largest moon, discovered by William Lassell in 1846, just 17 days after Neptune itself. It is the only large moon in the Solar System with a retrograde orbit, moving opposite to the direction of Neptune's spin. This suggests Triton was captured, likely from the Kuiper Belt.

When Voyager 2 flew past in 1989, it saw nitrogen geysers spraying dark material that left streaks on the surface. Parts of Triton's surface, called cantaloupe terrain, look like melon skin. Triton is among the coldest places measured in the Solar System, around minus 235 C.

Tidal forces are slowly pulling Triton inward. In the far future it will spiral close enough to be torn apart, possibly forming a ring around Neptune. Some scientists think it may hide an ocean beneath its icy shell.

What This Quiz Teaches

Space fans will enjoy these questions.

How Triton orbits
Where it came from
What Voyager saw
How cold it is
What its future holds

Did You Know?

Triton has a thin nitrogen atmosphere.
Its surface has few craters.
It is larger than Pluto.
Triton reflects much sunlight.
A mission called Trident was proposed.