Hydrogen is the most abundant element in the universe, accounting for about 75% of all matter. It is the lightest element and the simplest atom, consisting of a single proton and a single electron.

Helium is the second most abundant element in the universe, accounting for about 24% of all matter. It is a light, inert gas that is formed in the Big Bang and in the fusion reactions that power stars.

Hydrogen cyanide is the most abundant molecule in the universe, followed by water, carbon dioxide, and ammonia. It is a simple molecule that is formed from the reaction of hydrogen and carbon monoxide.

Nucleosynthesis is the process by which elements are formed in the universe. It occurs in stars, supernovae, and other high-energy environments. Nucleosynthesis can produce elements from hydrogen to uranium.

Supernovae are the primary mechanism by which elements are distributed throughout the universe. When a massive star dies, it explodes as a supernova, releasing its elements into the interstellar medium. These elements can then be incorporated into new stars and planets.

HD 140283 is the oldest known star in the universe, with an estimated age of 13.2 billion years. It is a metal-poor star located in the constellation Hercules.

GN-z11 is the most distant object ever observed in the universe, with a redshift of z = 11.1. It is a galaxy that existed about 13.4 billion years ago, just 400 million years after the Big Bang.

The solar system is composed primarily of hydrogen, helium, carbon, and oxygen. These elements make up the majority of the mass of the sun, planets, and other objects in the solar system.

The Earth's atmosphere is composed primarily of nitrogen, oxygen, argon, and carbon dioxide. These gases make up the majority of the mass of the atmosphere and are essential for life on Earth.

The Earth's crust is composed primarily of silicon, oxygen, aluminum, and iron. These elements make up the majority of the mass of the crust and are responsible for its composition and structure.

The Earth's mantle is composed primarily of oxygen, silicon, magnesium, and iron. These elements make up the majority of the mass of the mantle and are responsible for its composition and structure.

The Earth's core is composed primarily of iron, nickel, and sulfur. These elements make up the majority of the mass of the core and are responsible for its composition and structure.

The Moon is composed primarily of oxygen, silicon, aluminum, and iron. These elements make up the majority of the mass of the Moon and are responsible for its composition and structure.

Mars is composed primarily of oxygen, silicon, magnesium, and iron. These elements make up the majority of the mass of Mars and are responsible for its composition and structure.

Jupiter is composed primarily of hydrogen, helium, carbon, and oxygen. These elements make up the majority of the mass of Jupiter and are responsible for its composition and structure.