universe We know that the universe is around 13.8 billion years old, but how?
Stars, galaxies, stellar remnants, and other things with ages spanning billions of years are disperse throughout space. The cosmos is thought to be 13.8 billion years old, which is an almost unfathomable amount of time.
How do we know, though? Scientists disagree frequently on the universe’s age, but they can (slightly) estimate it by analyzing light and other forms of space radiation.
In the 1920s, astronomer Edwin Hubble calculate the distance of an object based on the time it takes for light to reach Earth, and the speed of travel based on how much light coming from a great distance is red shift.
also develop a method to determine the relationship between Or move to the low-energy (or red) end of the electromagnetic spectrum.
This quantity, now known as the Hubble constant, indicates how the cosmos is expanding in various places. NASA (opens in new tab) claims that the Hubble constant is greater for distant objects and vice versa,
indicating that the universe’s expansion is speeding. This discovery has the effect of making it more challenging to establish the universe’s estimated age.
The Hubble constant
The galaxies we discover in the Universe, at the greatest scales, follow a pretty straightforward relationship between the two observable qualities of distance and Redshift, where the farther an item is from us, the higher its measured Redshift will be.
Surprisingly, the law connecting them is really simple: the recession speed you would deduce from a galaxy’s Redshift equals that galaxy’s distance times the Hubble constant.
More astonishingly, that constant has essentially the same value for every galaxy we observe, especially for galaxies that are rather close to us—within a few billion light-years. Even