How do scientists determine the age of the universe?
They can determine the age of the universe using two main methods. The first one is by studying the oldest objects in the universe. The second is by measuring how fast it is expanding. Scientists have come to the realization that the universe cannot be older than the objects inside it. Astrologists can determine the age of the oldest stars, and thereby put a limit on the age of the universe.
How can we determine the age of stars?
The life cycle of a star is based on mass. Stars with a larger mass tend to burn faster than the lower mass stars. For example a star that is 10 times as massive as the sun will burn through its fuel supply in twenty million years, compared to a star that is half the sun’s mass which will last more than twenty billion years. The mass also affects the brightness and luminosity of a star.
Population III stars
The first stars are known as population III stars. They were very large in size, but short lived. These stars were made up of only hydrogen and helium, but with fusion, there were elements created that would help to build the next stars that would be present in the future. These were the stars that formed the first heavy atoms that allowed humans to be here. The detection of dust in the early universe provides new information on when the supernova exploded and when the first stars appeared. Scientists say “determining the time of this cosmic dawn allows us to determine the age of the universe and ultimately be found through the study of interstellar dust.
Expansion of the universe
The universe is constantly expanding. If scientists know the rate of expansion they can work backwards to determine the age of the universe. A number of different factors determine the value of this constant. Scientists must determine the proportion of regular and dark matter to dark energy. As of 2019, the age of the universe is 14 billion years old.