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Planets Word Search

Free printable planets word search puzzles: explore the Solar System through planets, moons and space vocabulary, from a beginner grid to real astrophysics.

Editorial review

Reviewed according to the Modern Word Search methodology.

Reviewed by Modern Word Search Editorial Team · August 2026. First published August 2026. Next scheduled review: Winter 2027.

Easy

Planets — Easy Word Search

Grid size12x10
Words to find10
Font size16 pt
PaperA4 & US Letter
Answer keyIncluded
Puzzle IDP-E-029 · v2026.3

All eight planets of the Solar System, plus the Sun and Moon — the complete beginner set every student learns first.

The shortest words ("sun" and "mars") help new solvers gain confidence quickly, while longer entries such as "neptune" and "jupiter" encourage them to scan the whole grid instead of stopping after the first few finds. In total, this puzzle hides 10 words (earth, mars, venus, mercury, saturn, uranus, neptune, jupiter, moon, sun) across a 12x10 grid, using 10 of its 16 unique letters at least twice.

Why we chose this word list

We kept Pluto out on purpose: since its 2006 reclassification as a dwarf planet, we teach the eight-planet model accurately rather than the nine most solvers grew up with.

Every planet name here is also its own memorable word, so this puzzle doubles as an order-of-the-planets memory exercise.

Vocabulary analysis

Measured directly from this puzzle's own grid — not a generic estimate.

10Words
5.4Average length
3Shortest word
7Longest word
16Unique letters
10Repeated letters
45.0%Grid coverage
0.10Word overlap score
2–5 minEstimated solving time

Why this level is easy

  • Only horizontal and vertical words — no diagonals
  • No reversed words
  • Short, everyday vocabulary
  • No uncommon spellings
  • Minimal overlaps between words

This puzzle satisfies every requirement of our easy level, as defined in our published methodology and applied consistently across every easy puzzle on this site.

Medium

Planets — Medium Word Search

Grid size15x15
Words to find15
Font size13 pt
PaperA4 & US Letter
Answer keyIncluded
Puzzle IDP-M-029 · v2026.3

Fifteen words for the objects and forces that shape planets, moving past naming them into how they actually behave in space.

The shortest words ("axis" and "comet") help new solvers gain confidence quickly, while longer entries such as "satellite" and "atmosphere" encourage them to scan the whole grid instead of stopping after the first few finds. In total, this puzzle hides 15 words (asteroid, meteor, comet, galaxy, eclipse, orbit, rotation, atmosphere, gravity, telescope, satellite, crater, equator, axis, nebula) across a 15x15 grid, using 17 of its 21 unique letters at least twice.

Why we chose this word list

We distinguished "asteroid", "meteor" and "comet" deliberately — three genuinely different objects often used interchangeably, which this puzzle treats correctly.

"Axis" and "rotation" are paired because a planet's tilt on its axis, not just its rotation, is what actually causes seasons — a common misconception worth correcting.

Vocabulary analysis

Measured directly from this puzzle's own grid — not a generic estimate.

15Words
6.9Average length
4Shortest word
10Longest word
21Unique letters
17Repeated letters
45.8%Grid coverage
0.33Word overlap score
7–13 minEstimated solving time

Why this level is medium

  • Horizontal, vertical and diagonal words
  • No reversed words
  • Mixed word lengths, some less common vocabulary
  • Moderate overlaps between words

This puzzle satisfies every requirement of our medium level, as defined in our published methodology and applied consistently across every medium puzzle on this site.

Hard

Planets — Hard Word Search

Grid size20x20
Words to find20
Font size11 pt
PaperA4 & US Letter
Answer keyIncluded
Puzzle IDP-H-029 · v2026.3

Twenty terms from real orbital mechanics and planetary formation — perihelion, accretion, eccentricity — the vocabulary an astronomy course actually uses.

The shortest words ("orbital" and "aphelion") help new solvers gain confidence quickly, while longer entries such as "gravitational" and "magnetosphere" encourage them to scan the whole grid instead of stopping after the first few finds. In total, this puzzle hides 20 words (heliocentric, elliptical, gravitational, magnetosphere, revolution, astronomical, celestial, planetesimal, accretion, luminosity, perihelion, aphelion, eccentricity, astrophysics, interstellar, exoplanet, habitable, terrestrial, orbital, rotational) across a 20x20 grid, using 18 of its 19 unique letters at least twice.

Why we chose this word list

"Perihelion" and "aphelion" are the precise terms for a planet's closest and farthest points from the Sun — exact vocabulary, not simplified synonyms for "near" and "far".

"Exoplanet" and "habitable" are included together since the search for potentially habitable exoplanets is one of the most active areas of current astronomy research.

Vocabulary analysis

Measured directly from this puzzle's own grid — not a generic estimate.

20Words
10.5Average length
7Shortest word
13Longest word
19Unique letters
18Repeated letters
52.5%Grid coverage
0.35Word overlap score
17–33 minEstimated solving time

Why this level is hard

  • All eight directions, including reversed words
  • Longer, denser word list
  • Similar-looking decoy letter sequences in the filler
  • Frequent overlaps between words

This puzzle satisfies every requirement of our hard level, as defined in our published methodology and applied consistently across every hard puzzle on this site.

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