crossword

5. Regions of space, typically within nebulae, where gas and dust come together under gravity to form new stars.
8. A vibration that travels through a medium, such as air or water, and can be heard when it reaches a person's or animal's ear.

1. The plural form of nebula, referring to multiple clouds of gas and dust in space that are sites of star formation or remnants of exploded stars.
2. A vast cloud of gas and dust in space, often illuminated by nearby stars, where new stars and planetary systems can form.
3. The number of occurrences of a repeating event per unit of time, commonly used to describe the number of wave cycles that pass a fixed point per second, measured in hertz (Hz).
4. Large, rigid pieces of Earth's lithosphere that move and interact at their boundaries, causing geological activities such as earthquakes, volcanic eruptions, and mountain formation.
6. The study of the structure and movement of Earth's lithosphere, including the processes that shape the planet's surface, such as plate tectonics and mountain building.
7. The maximum extent of a vibration or displacement of a wave, measured from its equilibrium position, often related to the loudness of sound or the intensity of a signal.