TIMELINE

The history of our universe began with the Planck era, which lasted from 10⁻⁴³ seconds to 10⁻³⁶ seconds after the Big Bang. During this time, the universe was incredibly hot and dense, with temperatures reaching up to 10³² degrees Celsius. At this point, the four fundamental forces of nature (gravity , electromagnetism, the strong nuclear force , and the weak nuclear force) were unified into one force.

As the universe expanded and cooled, the four forces began to separate, with gravity becoming the weakest of the four. At around 10⁻¹² seconds, the universe entered the Grand Unification Era, where the strong and weak nuclear forces were unified.

The universe continued to expand and cool, and at around 10⁻⁶ seconds, the universe entered the Electroweak Era, where the electromagnetic and weak nuclear forces were unified. This era lasted until around 10⁻¹⁰ seconds.

As the universe expanded and cooled further, protons and neutrons began to form, followed by the creation of atoms. This era, known as the era of Nucleosynthesis, lasted until around 380,000 years after the Big Bang.

After this point, the universe became transparent, allowing light to travel freely. This era, known as the era of Recombination, marked the beginning of the cosmic microwave background radiation that we can still observe today.

As the universe continued to expand and cool, gravity pulled together matter to form clumps, which eventually became the first stars and galaxies. This era, known as the era of structure formation, lasted until around one billion years after the Big Bang.

The formation of stars and planets followed this era, with the first stars forming around 200 million years after the Big Bang. According to the latest findings from the images of the JWST perhaps from 150 My. (These stars were massive and short-lived, and their death explosions seeded the universe with the heavy elements necessary for the formation of planets like Earth.

Our solar system formed around 4.6 billion years ago, and life on Earth appeared around 3.5 billion years ago.

The ongoing process of star and planet formation continues to shape the universe to this day.

phys.org

NASA

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Our Sun and its 10 nearest neighbors are shown in this diagram with their relative sizes to scale. Their masses and radii are given in solar masses (M☉) and solar radii (R☉); magnitudes listed are visual (V) magnitudes. [2]