Common Errors Grammar Tip 38

Celestial capitalization 

Which sentences are correct?

1. I love to lie in the sun.
2. I love to lie in the Sun.

3. The sun is a yellow dwarf star.
4. The Sun is a yellow dwarf star.

5. Jupiter has 101 moons.
6. Jupiter has 101 Moons.

7. There was a full moon last night.
8. There was a full Moon last night.

9. The last time men walked on the moon was 1972.
10. The last time men walked on the Moon was 1972.

11. Earth is the third planet from the Sun.
12. The Earth is the third planet from the Sun.

13. I love the smell of the earth after a rain shower.
14. I love the smell of the Earth after a rain shower.

15. The solar system formed 4.6 billion years ago.
16. The Solar System formed 4.6 billion years ago.

17. There is only one known universe.
18. There is only one known Universe.

The correct sentences are A, D, E, G, J, K, M, P, Q, and R.

Why?

Capitalize the terms when they function as proper nouns. For example, the Sun is the name of the celestial body around which Earth revolves. Use all lowercase letters when the terms function generically or descriptively. For example, with a lowercase s, the sun means “sunlight.” You definitely want to lie in the sun, not in the Sun!

The Moon is the name of the celestial body that orbits Earth. All other moons are lowercase. The same rule applies to the Sun—only ours is capitalized. All others are lowercase.

The name of our planet is Earth, not “the Earth.” Lowercase earth means “dirt” or “soil.”

The one and only Solar System consists of the Sun and the bodies that orbit it, including planets, dwarf planets, moons, asteroids, and comets. Our Solar System is one of the estimated billions of planetary systems that make up our galaxy, the Milky Way. A planetary system includes all the celestial bodies that orbit a central star or star system. A star system is made up of two or more stars that orbit each other.

The universe includes everything—all stars, all planets, all galaxies, and intergalactic space. Usually lowercase, in the same fashion as “the world,” the term is capitalized as a name in some scientific journals.

To summarize, the names Sun, Moon, and Earth appear in lowercase when used generically or descriptively. The name Solar System is always capitalized. Its generic equivalent is planetary system. The universe may or may not be capitalized, depending on style. Choose one form or the other, and use it consistently.