1. Uranium: Named after the planet Uranus, discovered in 1781.

2. Neptune: Named after the planet Neptune, discovered in 1846.

3. Helium: Named after the Greek word "helios", meaning sun, as it was first discovered in the sun's spectrum.

4. Promethium: Named after Prometheus, a Titan in Greek mythology who stole fire from the gods, referencing the element's use in nuclear technology.

5. Cerium: Named after the dwarf planet Ceres, discovered in 1801.

Let me know if you'd like to know more about any of these elements!