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  2. Stellar evolution - Wikipedia

    en.wikipedia.org/wiki/Stellar_evolution

    Representative lifetimes of stars as a function of their masses The change in size with time of a Sun-like star Artist's depiction of the life cycle of a Sun-like star, starting as a main-sequence star at lower left then expanding through the subgiant and giant phases, until its outer envelope is expelled to form a planetary nebula at upper right Chart of stellar evolution

  3. Chronology of the universe - Wikipedia

    en.wikipedia.org/wiki/Chronology_of_the_universe

    These stars were the first source of visible light in the universe after recombination. Structures may have begun to emerge from around 150 million years, and early galaxies emerged from around 180 to 700 million years. [citation needed] As they emerged, the Dark Ages gradually ended. Because this process was gradual, the Dark Ages only ended ...

  4. Age of the universe - Wikipedia

    en.wikipedia.org/wiki/Age_of_the_universe

    The other is based on the distance and relative velocity of a series or "ladder" of different kinds of stars, making it depend on local measurements late in the history of the universe. [2] These two methods give slightly different values for the Hubble constant , which is then used in a formula to calculate the age.

  5. List of oldest stars - Wikipedia

    en.wikipedia.org/wiki/List_of_oldest_stars

    The age of the oldest known stars approaches the age of the universe, about 13.8 billion years. Some of these are among the first stars from reionization (the stellar dawn), ending the Dark Ages about 370,000 years after the Big Bang. [1] This list includes stars older than 12 billion years, or about 87% of the age of the universe.

  6. Timeline of knowledge about galaxies, clusters of galaxies ...

    en.wikipedia.org/wiki/Timeline_of_knowledge...

    5th century BC – Democritus proposes that the bright band in the night sky known as the Milky Way might consist of stars. 4th century BC – Aristotle believes the Milky Way to be caused by "the ignition of the fiery exhalation of some stars which were large, numerous and close together" and that the "ignition takes place in the upper part of the atmosphere, in the region of the world which ...

  7. Timeline of the early universe - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the_early_universe

    600 million years: HE 1523-0901, the oldest star found producing neutron capture elements forms, marking a new point in ability to detect stars with a telescope. [9] 630 million years (z = 8.2): GRB 090423, the oldest gamma-ray burst recorded suggests that supernovas may have happened very early on in the evolution of the Universe [10]

  8. History of astronomy - Wikipedia

    en.wikipedia.org/wiki/History_of_astronomy

    The Northern Hemisphere page from Johann Bayer's 1661 edition of Uranometria - the first atlas to have star charts covering the entire celestial sphere Southern Hemisphere. The history of astronomy focuses on the contributions civilizations have made to further their understanding of the universe beyond earth's atmosphere. [1]

  9. Timeline of the far future - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the_far_future

    The time by which all stars in the universe will have exhausted their fuel (the longest-lived stars, low-mass red dwarfs, have lifespans of roughly 10–20 trillion years). [9] After this point, the stellar-mass objects remaining are stellar remnants (white dwarfs, neutron stars, black holes) and brown dwarfs.