The article discusses the hypothetical planet, Theia, which scientists believe may have collided with young Earth around 4.5 billion years ago. This collision is thought to have released enough material that condensed to form the Moon, which plays a critical role in stabilizing Earth's rotation. Without this cosmic event, the author highlights that life, as we know it, might not exist today, leading to reflections on the significance of such events in shaping planetary systems.

The article elaborates on the so-called giant impact hypothesis, wherein Earth experienced a massive collision with a Mars-sized object, resulting in the debris that became the Moon. The significance of this collision extends beyond mere lunar formation; it also set in motion a gravitational interplay between the Earth and the Moon, stabilizing Earth's axial tilt over billions of years. This stability is crucial for maintaining a climate conducive to life, emphasizing the Moon's integral role in the development of Earth's biosphere.

In essence, Theia's collision with Earth is depicted as a pivotal event in cosmic history, with far-reaching implications for the evolution of life on our planet. The piece invites readers to consider the vast timelines and transformative events that shaped their existence, reminding us that the Moon's presence is not merely a celestial phenomenon, but a fundamental aspect of our planet's dynamic system.