How old is the Universe 2018?: Isn’t it funny how we celebrate our birthdays each year and mature with age, but still have no clue about how old our own universe is? Although, age may be looked upon as just a number, nevertheless when it comes to our universe it is quite a ponderous situation. Various researchers have collaborated to one finite result, which clearly states that the universe we reside in is 13.8 billion years old. But, how can that be possibly deciphered? We count our age from the year we were born, but that is not definite when it comes to the universe. Then how did researchers reach this conclusion? Let’s have a look as to how the age of the universe was determined.
Knowing about Age Limits
Just like how children cannot be older than their parents, similarly, the universe cannot be inferior to the bodies which it contains in terms of their age. Applying the absolute same principal, scientists and researchers started with determining the age of the oldest stars present to resolve the age limit of the universe.
From its birth to its closure, a stars entire life is determined by its mass. Now, there were a group of stars popular by the name of Population III stars, these were observed as the first immense but short-lived stars. These were fabricated by hydrogen and helium gases, and further, their fusion gave birth to certain elements that subsequently aided the production of the next generation of stars.
However, Population III stars aren’t the only age determiners for the universe. There are some other bodies known as globular clusters which carry the same characteristics as Population III stars. The oldest amongst these have been traced to be living for 18 billion years.
The Expansion of our Universe
The universe is not flat; rather, it is always developing although the rate of this development is unknown. However, there exists something known as the Hubble Constant; this is a fundamental term used when it comes to the characterization of the universe. Now, the variables used to determine the value of Hubble Constant are finite, these include- the most prominent matter found in the universe, the ratio of dark matter to dark energy, and the density. Missions namely- Wilkinson Microwave Anisotropy Probe launched by NASA and the Planck spacecraft by the European Space Agency help in deducing these factors by calculating the amount of thermal radiation residue post the Big Bang explosion.