Across
- 3. This characteristic explains why the outer planets are much colder than the inner planets (4 words, no spaces - Answer in this format: ______________the_____)
- 4. An astronaut standing on this type of planet would sink right through the surface because these worlds are composed entirely of liquids and gases (two words, no spaces)
- 7. A satellite made of rock and ice that orbits a planet
- 8. This zone between two planets acts like a cosmic junkyard, filled with chunks of rock and metal that never formed into a planet (two words, no spaces)
- 10. Scientists study this material floating in space because it's the building blocks that will eventually become new planets and stars (two words, no spaces)
- 14. This type of solar system object originates from the Kuiper Belt and has a highly elliptical orbit
- 17. A system of eight planets and the sun, along with moons, asteroids, and comets (two words, no spaces)
- 20. When a space rock actually makes it all the way to Earth's surface without burning up, scientists call it this
- 21. Unlike planets, this type of object hasn't cleared its orbital neighborhood but still orbits the Sun and has enough mass to be roughly round (two words, no spaces)
- 24. Our solar system is located in this part of the Milky Way, not in the center, but on one of the ____________ arms
- 25. This type of galaxy has no spiral arms and looks like a giant, smooth oval of stars in space (two words, no spaces)
- 28. You see a bright streak across the night sky, but by the time you point it out to your friend, it's gone
- 29. Another name for the outer planets like Jupiter
- 32. This galaxy type has no organized structure and looks like a chaotic cloud of stars scattered randomly through space (two words, no spaces)
- 34. This celestial object appears huge to us only because of its proximity, but compared to other similar objects in the universe, it's actually quite average in size
- 36. This small celestial object was reclassified in 2006 because it couldn't clear other objects from its orbital neighborhood
- 37. Earth is unique among the inner planets because it has exactly this many natural satellites
- 39. This is the only planet in our solar system that rotates on its side, rolling like a ball as it orbits the Sun
Down
- 1. If you could somehow turn on a giant flashlight in space, this type of light from cosmic dust would be invisible to your eyes but detectable by special cameras (two words, no spaces)
- 2. Part of a spiral galaxy where the oldest stars live
- 5. This planet's day is longer than its year, it has a thick atmosphere compared th the other planet it is closest to, and it spins backwards compared to most other planets
- 6. The famous mnemonic My Very Excited Mother Just Served Us Nachos helps students remember this specific sequence (3 words, no spaces - Answer in this format: _______of_______)
- 7. If you traveled to the edge of our galaxy and looked back, you would see this spiral-shaped structure that contains our entire solar system (3 words, no spaces)
- 9. Chunks of rock in space that orbit the sun
- 11. These four planets are called terrestrial because they have solid, rocky surfaces you could actually stand on (two words, no spaces)
- 12. When this icy visitor approaches the Sun, it develops a glowing tail, but when it's far away, it's just a frozen chunk in space
- 13. A huge system that includes gas, dust, billions of stars, and objects orbiting the stars
- 15. This red planet has two tiny moons named after the Greek words for fear and panic
- 16. A huge ball of extremely hot matter in space that gives off energy
- 18. Scientists can determine a planet's composition by studying this property, which explains why gas giants have much lower values than rocky planets
- 19. All planets follow this curved path around the Sun, held in place by gravitational force
- 20. Pieces of asteroids that break off, so they are smaller, and can be found in the asteroid belt
- 21. This measurement tells us how wide a planet is from one side to the other through its center
- 22. These two inner planets are unique because they completely lack natural satellites, unlike their neighboring rocky worlds (3 words, no spaces - Answer in this format: _______and__________)
- 23. This fundamental property of matter explains why larger planets have stronger gravitational fields and can capture more moons
- 26. If Earth were the size of a basketball, this planet would be about the size of a small marble and be the closest to our star
- 27. A star appears bright in our sky for two main reasons: its actual brightness and this crucial factor related to space
- 30. If you could visit the center of any gas giant, you would find this solid structure surrounded by layers of liquid and gas
- 31. This natural or artificial object orbits Earth or another planet, like our Moon or the International Space Station
- 33. This force explains why Jupiter has over 80 moons while Mercury has none, and it's directly related to the amount of matter an object contains
- 35. This planet has the most spectacular ring system visible from Earth, made of countless ice and rock particles
- 38. This distant blue planet has winds reaching 1200 mph, the fastest in the solar system