| 100% | RINGS | 5 | Feature of the planet Saturn closely studied by NASA's Cassini mission |
| 35% | MARSODYSSEY | 11 | NASA's unmanned mission to the Red Planet launched in 2001, named in honor of an Arthur C. Clarke novel |
| 34% | GAS | 3 | Much of the planet Saturn |
| 33% | CRUST | 5 | Feature of the inner planets |
| 33% | ARTEMIS | 7 | NASA's moon missions of the 2020s |
| 32% | DUNES | 5 | Features of the sci-fi planet Arrakis |
| 32% | GEOGRAPHY | 9 | The study of Earth's features and places |
| 30% | AREOLOGY | 8 | The study of the Greek god of war's planet |
| 29% | EARDRUM | 7 | Part of the body studied by otolaryngologists |
| 29% | ASTRONOMY | 9 | The study of stars and planets |
| 29% | TILT | 4 | Feature of the earth's axis |
| 29% | CRATERS | 7 | Features of the moon's surface |
| 28% | OROGRAPHY | 9 | Study of the formation and features of mountains |
| 28% | ASTRO | 5 | Study of the stars and planets, for short |
| 28% | ASTRONOMY | 9 | The study of planets and other objects in space |
| 28% | ASIA | 4 | About 30% of the planet's land |
| 28% | ELEKTRA | 7 | Novel by Jennifer Saint that's a retelling of Greek myths featuring the daughter of Agamemnon |
| 27% | TILT | 4 | Feature of the earth's axis that causes the seasons |
| 27% | DATED | 5 | Marked by features of the immediate and usually discounted past |
| 27% | ROTUNDAS | 8 | Features of the U.S. Capitol and Rome's Pantheon |
| 27% | GEOGRAPHY | 9 | The study of the Earth and its features |
| 27% | BASSSOLO | 8 | Prominent feature of the Who's "My Generation" |
| 27% | BASSSOLO | 8 | Iconic feature of the Who's "My Generation" |
| 27% | ARIADNE | 7 | Novel by Jennifer Saint that's a retelling of Greek myths featuring the children of King Minos |
| 27% | APES | 4 | "War for the Planet of the ___" (2017 sequel featuring Andy Serkis as Caesar) |
| 27% | ALAMO | 5 | The —, Texan mission; site of an 1836 siege by Mexican forces |
| 27% | JUPITER | 7 | "Drops of ___ (Tell Me)," 2001 song by Train with the Solar System's largest planet in its title |
| 26% | HAREANDCANDLING | 15 | Features of the Easter Bunny's checking each 36-Down for freshness? |
| 26% | NATURAL | 7 | With 39-Across, subject of study represented literally by the words spelled out by this puzzle's circled letters |