The Big Bang Timeline
In a cataclysmic event, a Mars-sized object named Theia collided with the early Earth, sending massive amounts of debris into orbit. This debris coalesced over time to form the Moon, which eventually became tidally locked to the Earth, stabilizing the planet’s axis and paving the way for the development of life. The Moon is comprised […]
Visual Craters of the Moon! In a period known as the Late Heavy Bombardment, the solar system experienced a intense barrage of asteroid and comet impacts, with many large objects striking the Earth and Moon. This event likely occurred as the giant planets Jupiter and Saturn migrated to their current orbits, sending smaller bodies into
Late Heavy Bombardment Read More »
GOE: The Great Oxidation Event started enriching the atmosphere with oxygen beginning around 2.4 billion years ago. It marked one of Earth’s most dramatic transformations. Initiated by the widespread activity of photosynthetic cyanobacteria, this period, known as the Great Oxidation Event, gradually saw the accumulation of oxygen that was initially absorbed by oceanic iron. As
Third Atmosphere: Oxygen Atmosphere Read More »
Deep orange or reddish-brown atmosphere: The second atmosphere’s formation was crucial and occurred just before or alongside the formation of Earth’s oceans, which directly supported the evolution of organic molecules and prebiotic microenvironments. The second atmosphere began to develop around 4.5 to 4 billion years ago, as volcanic outgassing released gases trapped in the Earth’s
Second Atmosphere: Carbon Dioxide & Nitrogen Read More »
Likely white or grayish atmosphere: The first atmosphere developed first but was not directly involved in the development of life. The first atmosphere formed shortly after Earth’s formation around 4.5 billion years ago. This initial atmosphere was primarily composed of hydrogen and helium, the lightest and most abundant elements in the universe, which were captured from
First Atmosphere: Hydrogen & Helium Read More »
As the Earth cooled following its formation, outgassing from volcanic activity released water vapor and other gases into the atmosphere. When the Earth’s surface cooled sufficiently, this water vapor condensed and fell as rain, filling the basins that would become oceans.
First Oceans: Fresh Water Read More »
The process of salination likely began soon after the oceans formed but took hundreds of millions of years to reach the salinity levels similar to what we see today. The oceans were likely significantly salty by about 3.5 billion years ago. Salinity increased primarily through the weathering of rocks and the leaching of minerals (including
Second Oceans: From Fresh to Salty Read More »
The synthesis of simple organic molecules such as formaldehyde (H₂CO), methanol (CH₃OH), and simple hydrocarbons in the dense molecular clouds of the interstellar medium occured once sufficient carbon was present. This process has been ongoing for billions of years but became more prevalent as the universe aged and more carbon became available. Big History Thresholds:
Interstellar Clouds: Organic Molecules Read More »
The chemical evolution from inorganic precursors to organic molecules is a fascinating story of transformation driven by Earth’s dynamic early conditions and possibly assisted by the input from space in the form of meteorites rich in organic compounds. During this period, the Earth witnessed a series of complex chemical reactions facilitated by its primordial atmosphere,
Inorganic Precursors to Organic Molecules Read More »
30 Phil, Chapter 1 Touchstone 1 of 80: Big Bang. Immediately following the state of the singularity, the universe entered a phase of rapid expansion and cooling, known as the Big Bang Expansion. This critical period signifies not an explosion in space but the very expansion of space itself, from an incomprehensibly dense point known
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Alongside or following the chemical evolution of organic molecules, the formation of prebiotic microenvironments, such as hydrothermal vents or warm little ponds, provided niches where concentrations of organic molecules could interact. These environments could have been crucial for the assembly of complex organic molecules and the initiation of catalytic cycles.
Formation of Prebiotic Microenvironments Read More »
While the 4.4 billion years ago is a guess as to when these processes might have started, the 4.1 billion years ago guess is a better representatoin of current understanding on when the needed building blocks of life evolved. Before the appearance of self-replicating molecules, there was a crucial phase of chemical evolution where simple
Chemical Evolution of Organic Molecules Read More »
The formation of cellular membranes represents a pivotal development in the pre-life world, enabling the creation of defined boundaries for primitive cells. These membranes, likely formed from simple lipid bilayers, provided a controlled environment for chemical reactions and played a critical role in the emergence of the first cell-like structures, distinguishing them from their surrounding
Cellular Membranes Read More »
The constellations we recognize today will be vastly different in a million years due to what astromers call “proper motion” of stars. This will transform our night sky, creating new constellations from stars that have shifted positions, presenting future astronomers with a completely new celestial map to study. Because of stellar motion, our current Star
Brand New Constellations Read More »
The Lambda Cold Dark Matter model of the universe predicts a Big Freeze. The Big Freeze is projected sometime after 10100 years from now. That’s a set of googol years from now. After billions is trillions then quadrillion. After quadrillions is Quintillion, Sextillion, Septillion, Octillion, Nonillion, Decillion, and finally a GOOGOL. This number is beyond
Lambda Model: Heat Death of the Universe Read More »
Over an incredibly long timescale, the Sun’s white dwarf remnant could cool enough to become a black dwarf, a theoretical stellar remnant that emits no light. Although speculative, theoretical models give us insight into the lifespan of the Sun as a white dwarf. After transitioning into a white dwarf, the Sun is expected to cool
After shedding its outer layers and engulfing the inner planets during its red giant phase, the Sun will leave behind a white dwarf. The remaining material could potentially form a new planetary system around this white dwarf.
Formation of a New Solar System Read More »
The Milky Way and Andromeda galaxies are expected to collide and merge into a single elliptical galaxy. Despite the dramatic nature of this event, the vast distances between stars mean that direct stellar collisions are unlikely.
Milky Way-Andromeda Collision Read More »
Current scholarship generally places the formation of the Milky Way between 200 and 600 million years after the Big Bang, during the period of early galaxy formation that followed the forging of Population II stars. Some of the oldest stars within the Milky Way belong to this Population II category, with estimates for their formation
Birth of the Milky Way Read More »
Current observations, such as those of GN-z11, suggest that galaxy formation began as early as 400 million years after the Big Bang. This galaxy, observed at a redshift of z=11.09, stands as a testament to the rapidity with which the universe’s first structures began to coalesce from the primordial gas. While the detection of GN-z11
