How big is the size of the universe?
Our universe is infinite, there is no end to it. However, the diameter of the observable universe is about 93 billion light-years. How big is our earth in the size of this universe? Our moon looks very close to the earth.
But it is 3 lakh 84 thousand kilometers from its distance. 30 Earths will fit comfortably in both of these gaps.
If we travel from the earth towards the moon from 100 km/hr, it will take 160 days to reach the moon. Our earth looks like this from the moon.
But when viewed from Mars, the shape of the earth is seen as a dot. This distance is so much that the light takes 20 minutes to reach the earth.
The man-made space probe Voyager 1 present has 140 AU from us. This makes the earth look like this.
If we zoom out our solar system then we come to the interstellar and we do it in distance measure light year.
The nearest star from the sun is Alpha Centauri. Whose distance is 4.3 light-years from the sun? It will take 70000 years for Voyager 1 to reach this star.
And zooming out will show our Milkyway Galaxy, in which this small dot is our sun. Our Milky Way Galaxy has a distance of 10000 light-years from one corner to another. Which has a million stars and planets?
Zoom out the Milky Way, we will get a Local Group Galaxy which has 54 galaxies like Milky Way Galaxy. Whose size are 10 million light-years from one corner to another?
Zooming it out too, we get the Virgo supercluster in which our local group is a small part of the Galaxy.
The distance of Virgo supercluster from one corner to the other is 110 million light-years. But the size of the universe is even bigger.
Zooming it out too, we get the laniakea supercluster in which the size of the Virgo supercluster is as much as the grains of sand.
The size of laniakea supercluster is 520 light-years.
And if you zoom it out too, the laniakea supercluster is a small part of the observable universe whose size is 93 billion light-years.
This does not mean that this is the size of the universe. This is so far as humans have discovered.
Observable universe vs the Entire universe
There are two parts of the Universe, one is the observable Universe which has been discovered by Science and the other is the Whole Universe.
According to the cosmic inflation theory, the size of the Whole Universe can be 150 sextillion times more than the observable universe.