| 100% | NITROGEN | 8 | This gas makes up around 78% of Earth's atmosphere |
| 70% | NITROGEN | 8 | 78% of Earth's atmosphere is made of this gas |
| 55% | NITROGEN | 8 | Gas that makes up most of Earth's atmosphere |
| 52% | ARGON | 5 | Noble gas that makes up almost 1% of the Earth's atmosphere |
| 52% | ARGON | 5 | Noble gas that makes up nearly 1% of the earth's atmosphere |
| 49% | ARGON | 5 | It makes up nearly 1% of the Earth's atmosphere |
| 45% | NITROGEN | 8 | This element makes up 78% of the air you breathe |
| 44% | HYDROGEN | 8 | Gas that makes up around 74 percent of the Sun |
| 44% | HELIUM | 6 | Gas that makes up around 24 percent of the Sun |
| 44% | OXYGEN | 6 | Air is made up of mostly nitrogen and this gas |
| 44% | AIR | 3 | Oxygen makes up only one-fifth of this on the earth |
| 42% | NITROGEN | 8 | Earth's atmosphere is 78% this element |
| 40% | NITROGEN | 8 | Element making up most of the world's atmosphere |
| 39% | WATER | 5 | It makes up 71% of the Earth's surface |
| 38% | ARGON | 5 | About 1% of Earth's atmosphere, and a phonetic hint to this puzzle's gimmick |
| 37% | YEAR | 4 | 365 days make up one of these |
| 36% | NEBULA | 6 | Space cloud, made up of gases and dust |
| 36% | ISLANDS | 7 | Hawaii is made up of these land masses |
| 36% | RUSSIA | 6 | Siberia makes up about 77 percent of this country |
| 35% | MEGABYTE | 8 | 1,024 KB make up this unit of computer information |
| 34% | ATM | 3 | ___osphere : layer of gases around the Earth |
| 34% | MOLTEN | 6 | Much of the rock around the Earth's core is this |
| 34% | ATOMS | 5 | John Dalton (1766-1844) theorized that matter was made up of these |
| 33% | URIC | 4 | Build up of this acid around joints can cause gout |
| 32% | CIRCLESBACK | 11 | Brings up a prior topic … or a hint to making sense of the answers to this puzzle's starred clues |
| 32% | LAYER | 5 | Ozone ___ (part of Earth's atmosphere) |
| 32% | MINUTES | 7 | Sixty of these make up one hour |
| 32% | FELDSPAR | 8 | Rock-forming mineral that makes up over half of the earth's crust |
| 31% | OCEAN | 5 | Around 70% of the earth's surface |
| 31% | GENE | 4 | It's made up of DNA |