| HERSCHEL | William --, astronomer who discovered Uranus in 1781 (8) |
| TOMBAUGH | Clyde William -; astronomer who discovered Pluto (8) |
| IDOMENEO | Opera by Mozart set in Crete that premiered in 1781 (8) |
| YORKTOWN | Site in Virginia, US where General Cornwallis surrendered to General Washington in 1781 (8) |
| ENGINEER | George Stephenson, born in 1781, was a noted English one (8) |
| CLYDE | US astronomer who discovered the dwarf planet Pluto in 1930 (5,8) |
| COMMANDMODULES | Order occasionally picked up about heading for Uranus in spacecraft |
| RHEA | Daughter of Uranus, in myth |
| TITANS | Giant children of Gaia and Uranus in Greek legend (6) |
| GAIA | Mother of Uranus in Greek mythology (4) |
| KEPLER | Johannes, German astronomer who discovered that planets move in elliptical orbits (6) |
| URANUS | Which planet was discovered by William Herschel in 1781 and named after the Greek god who was son an |
| GALILEO | Astronomer who discovered the main moons of Jupiter |
| HALL | Asaph, U.S. astronomer who discovered the moons of Mars (4) |
| CASSINI | Giovanni Domenico -; astronomer who discovered the gaps between Saturn's rings (7) |
| PHILIBERT | -- Jacques Melotte, British astronomer who discovered a moon of Jupiter (9) |
| LASSELL | Astronomer who discovered Neptune's moon Triton (7) |
| HUBBLE | Astronomer who discovered that the universe is expanding (6) |
| OPIE | John, painter who was launched in London in 1781 as 'the CornishWonder' (4) |
| ASPREY | William, English merchant who founded a silk printing business in 1781, later a luxury store (6) |
