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One of the most profound mysteries of modern astrophysics is the composition of our universe, which we discern through meticulous cosmic observations. These observations involve carefully analyzing light from distant galaxies, the behavior of galaxy clusters, and the cosmic microwave background radiation, which is the afterglow of the Big Bang.

Cosmic observations are also crucial in measuring phenomena that cannot be directly seen, such as dark matter and dark energy. By examining the way light bends as it travels through the universe—a phenomenon known as gravitational lensing—astronomers can infer the presence of dark matter. Similarly, the accelerated expansion of the universe, as observed by looking at distant supernovae, points to the existence of dark energy. These methods converge to paint a detailed picture of the universe's constituents beyond what is visible to us.

Through these and other observations, scientists have determined that dark energy is more prevalent in the universe than dark matter, fundamentally shaping the evolution and fate of the cosmos.

The universe is a complex tapestry woven with various forms of matter and energy. Normal matter, which includes stars, planets, and gases, makes up a mere fraction of the universe. It's the stuff of chemistry textbooks and what we interact with on a daily basis. However, the majority of the universe is composed of dark matter and dark energy, substances invisible to our current instruments but whose presence we infer from their profound effects on the cosmos.

Speaking of percentages, around 5% of the universe is made up of normal matter. Dark matter, despite being invisible, constitutes about 27%, acting as a cosmic scaffold for the structure of galaxies and clusters. The remaining 68% is dark energy, a mysterious force accelerating the expansion of the universe. The surprising discovery that dark energy is the dominant player in the universe’s composition is one of the most significant findings in recent cosmology, changing our fundamental understanding of the cosmos.

Without the gravitational force, the universe as we know it would not exist. Gravity shapes the structure of the cosmos, galaxies, stars, and even the trajectories of planets. The gravitational effects of matter that we cannot see, particularly dark matter, manifest in many observable ways. For instance, the rotational speeds of galaxies suggest there is more mass present than what we can detect with light alone, implying the existence of dark matter.

Gravitational lensing is another effect where the gravity from dark matter distorts the light from distant stars and galaxies, like a lens, indicating its presence. Dark energy, on the other hand, is associated with a gravitational effect that is less intuitive—it works against gravity, pushing galaxies apart and causing the universe to expand at an accelerating rate. This suggests that dark energy is a different kind of phenomenon, possibly an intrinsic property of space itself, and its effect on the large-scale structure of the universe is a research area of great interest and profound implications.