\(\mathbf{T} / \mathbf{F}:\) A cloud of interstellar gas is held together by gravity.

Gravity is one of the four fundamental forces in the universe. It is the force that attracts two bodies towards each other, proportional to their mass and the distance between them.
In space, gravity plays a critical role in the formation and behavior of celestial bodies. It governs the movement of planets, stars, moons, and interstellar clouds.
Even in the vast emptiness of space, gravity is always at work, pulling objects with mass towards each other. This invisible force ensures that galaxies hold together and our solar system remains intact.
Without gravity, matter in space would not coalesce into larger structures. This force is crucial for the existence and evolution of the universe as we know it.

Nebulae are enormous clouds of gas and dust scattered throughout space. They are the birthplaces of stars and act as cosmic nurseries.
These fascinating structures can vary in size, shape, and composition. Some nebulae are remnants of dead or dying stars, while others are regions where new stars are forming.
The primary components of nebulae are hydrogen, helium, and traces of other elements. They glow with stunning colors, usually due to the ionization of gases caused by nearby stars.
There are different types of nebulae, such as emission nebulae, reflection nebulae, and dark nebulae. Each plays a unique role in the lifecycle of stars and the evolution of galaxies.

Star formation is an intricate process that begins within the dense regions of interstellar clouds, called molecular clouds.
As gravity pulls particles within a nebula towards each other, the density increases, causing the temperature and pressure to rise at the core.
Once the core temperature becomes sufficiently high, nuclear fusion ignites, marking the birth of a new star. This process can take millions of years.
In the early stages, a protostar forms, which continues to accrete material from the surrounding nebula. Over time, this material falls onto the protostar, feeding its growth until it becomes a main-sequence star.
Star formation is essential for the creation of planets and other celestial bodies. The material left over from the star's formation can form planets, moons, asteroids, and comets, leading to the birth of a new solar system.
In summary, star formation is a pivotal process driven by gravity that leads to the creation of new stars and contributes to the ever-changing nature of the universe.