| ULTRAVIOLET | Type of radiation invisible to the human eye. Constant exposure to this radiation from the sun can be bad for the skin. |
| INFRARED | Radiation that is invisible to the human eye but we can sense as heat |
| INFRA | Range of light that's invisible to the human eye |
| OZONE | ____ layer, region of the upper atmosphere absorbing ultraviolet radiation from the sun (5) |
| SOLARENERGY | Radiation from the sun |
| ONUS | Nothing under the sun can make up for this burden |
| SOLO | Nothing under the sun can be alone! (4) |
| TURNTOASHES | Rheostat, affected by the sun, can burn up totally (4,2,5) |
| MERCURY | The phrase "mad as a hatter" was used to describe the behavior of hat makers suffering from poisoning caused by exposure to this material. (The Hatter in Alice's Adventures in Wonderland was a fiction |
| MACULA | Oval-shaped pigmented area in the centre of the retina of the human eye (6) |
| SOLARFLARE | A brief powerful eruption of intense high-energy radiation from the sun's surface |
| SOLARFLARES | Brief powerful eruptions of particles and electromagnetic radiation from the sun's surface (5,6) |
| GREENHOUSE | The ___ effect describes how the radiation from a planet's atmosphere warms the surface of that planet by preventing the heat from escaping into space |
| IRIS | The coloured muscular diaphragm that surrounds and controls the size of the pupil in a human eye (4) |
| TELESCOPIC | In a supermarket the French film is invisible to the naked eye (10) |
| ANGLIA | The type of car owned by Arthur Weasley, enchanted to make it fly and invisible to Muggles (6) |
| HOCK | Joint in the hind leg of a quadruped between the knee and fetlock, corresponding to the human ankle (4) |
| WHITE | Word used to describe noise containing all of the frequencies audible to the human ear (5) |
| GENA | Lateral part of an insect's head below the eye, analogous to the human cheek (4) |
| ATOMS | Particles invisible to the naked eye |
