With the beginning of the formation of the universe, the countdown began to a process that would ultimately create the appropriate conditions for the emergence of life on planet Earth.
While the future of the universe is thought to be very bleak, it is interesting so far. What happened since the formation of the universe?
1. It all started 13.7 billion years ago
The universe is believed to have begun about 13.7 billion years ago, during the “Big Bang.” We cannot be sure exactly when this happened, but we know that the universe is older than 13.5 billion years and younger than 14 billion years.
Different space missions have yielded slightly different estimates regarding the age of the universe. According to data collected by the European Space Agency's Planck mission between 2009 and 2013, the age of the universe is estimated at about 13.82 billion years.
Another estimate is based on observations from the Atacama Cosmology Telescope in Chile, which puts the universe at 13.77 billion years old.
2. Atoms formed about 380,000 million years after the “Big Bang”
Lighter subatomic particles such as quarks, electrons and neutrons are thought to have begun to form about 10 to 6 seconds after the Big Bang. However, temperatures were still too high for physics as we understand it today to exist.
However, shortly after 10 to 6 seconds, physicists believe the universe cooled enough for protons and neutrons to begin forming.
And after that, nothing really exciting happened for 380,000 million years. Around that time, the basic atom, hydrogen, began to form. At about the same time, some elements fused to form helium atoms.
3. The lights spread around the same time
As atoms began to form, energy in the form of light was released, creating what is today called the “cosmic microwave background,” where the absorption of free electrons made the universe transparent. Before this happened, the universe was dark because free electrons would scatter light (photons).
About 400 million years after the “Big Bang,” the universe emerged from the so-called “Dark Ages.” During this time, more accurately called the “era of reionization,” the universe went through a dynamic phase that is thought to have lasted until the universe was about a billion years old. However, recent observations suggest that reionization may have occurred much faster than scientists previously thought.
During this period, the gas clusters condensed enough to form the first stars and galaxies. The ultraviolet radiation from these energetic events removed and destroyed most of the surrounding neutral hydrogen gas.
4. Observing the first early stars
The Methuselah star, also named HD 140283, is known to be the oldest in the universe. It is located about 190.1 light-years from Earth in the constellation Libra, near the border with Ophiuchus in the Milky Way.
The age of Methuselah is estimated at more than 13 billion years, which is close to the age of the universe. However, the exact age remains unclear.
5. The discovery of two galaxies that formed after the Big Bang
In July of 2021, the James Webb Space Telescope (JWST) captured an image of a galaxy called GLASS-z13 that is believed to have formed about 300-400 million years after the “Big Bang.”
The James Webb Space Telescope also found another very early galaxy called GLASS-z11. Based on the mass of a billion suns, the research claims that both galaxies must be 500 million years old.
6. Our galaxy has a turbulent past
The Milky Way Galaxy is believed to have formed when massive clouds of gas and dust gathered under gravity. It is believed that the formation of our galaxy began with the formation of a spherical halo. Soon after, a bright, dense disc appeared.
However, recent research also suggests that things were not so simple. Its composition may have been very turbulent, including many collisions and mergers with smaller galaxies.
Data from the Gaia space observatory revealed that some of the oldest stars expected to be found in the galaxy's halo are already present in the disk. This indicates that the history of star movement and galaxy formation is more complex than previously thought.
The results indicate that the Milky Way is far from stationary. It evolved over billions of years, and was formed through gravitational interactions and mergers with other star systems. According to some astronomers, the Milky Way and the “neighboring” Andromeda Galaxy will collide in about 5 billion years.
7. It will all end in a cold and unglorious death or quite the opposite
Based on current evidence, the “Big Freeze” or “heat death” is perhaps the most likely scenario for the end of the universe. The universe may continue to expand indefinitely and eventually reach a state of maximum entropy (approaching absolute zero temperature).
At that point, with most of the gas exhausted, stars will stop forming, existing stars will burn out, and black holes will evaporate through what's called "Hawking radiation." This will lead to cold, black nothingness.
However, one theory points to the “Big Crunch,” a theory that suggests the universe may reverse its expansion and collapse into a hot, dense state. This could lead to another big explosion, starting the whole thing over again!
Although these theories are interesting, we will never know for sure what will happen, because our species will be long gone by then.
SpaceX launches a rocket carrying 25 satellites, including a South Korean spy satellite
The American company SpaceX launched a Falcon 9 rocket carrying 25 satellites.
The missile was launched from the Vandenberg base in the US state of California at 10:19 am, local time, on Friday.
Among the satellites carried by the missile are South Korea's first reconnaissance satellite "425 Project EO/IR", the first Irish satellite designed by University of Dublin students "EIRSAT-1", as well as the Armenian satellite "Hiasat-1".
South Korea launched its reconnaissance satellite 10 days after North Korea launched its own reconnaissance satellite.
South Korea intends to deliver 5 satellites into orbit until the end of 2025 for surveillance on North Korean territory.