Why can we see 46 billion light years?

The universe is about 13.8 billion years old, so any light we see has to have been travelling for 13.8 billion years or less – we call this the ‘observable universe’. However, the distance to the edge of the observable universe is about 46 billion light years because the universe is expanding all of the time.

How do they know the Universe is 13.7 billion years old?

We do not know the exact age of the universe, but we believe that it is around 13 billion years – give or take a few billion. Astronomers estimate the age of the universe in two ways: (a) by looking for the oldest stars; and (b) by measuring the rate of expansion of the universe and extrapolating back to the Big Bang.

Why did primordial nucleosynthesis stop?

By the time the Universe had cooled to a temperature of about 3 × 108 K after 1000 s, the particles had insufficient energy to undergo any more reactions. The era of primordial nucleosynthesis was at an end, and the proportion of the various light elements was fixed.

How much of universe can we see?

NEW YORK — All the stars, planets and galaxies that can be seen today make up just 4 percent of the universe. The other 96 percent is made of stuff astronomers can’t see, detect or even comprehend.

How many light years away can we see the universe?

Ask Ethan: How Can We See 46.1 Billion Light-Years Away In A 13.8 Billion Year Old Universe? Opinions expressed by Forbes Contributors are their own. The Universe is out there, waiting for you to discover it. radiation in a rapidly expanding state.

Is 92 billion light years big enough?

And so 92 billion light years might seem like a large number for a 13.8 billion year old Universe, but it’s the right number for the Universe we have today, full of matter, radiation, dark energy, and obeying the laws of General Relativity.

How old is the universe?

You might think, in a Universe limited by the speed of light, that would be 13.8 billion light years: the age of the Universe multiplied by the speed of light. But 13.8 billion light years is far too small to be the right answer.

How big is the universe?

You might think, in a Universe limited by the speed of light, that would be 13.8 billion light years: the age of the Universe multiplied by the speed of light. But 13.8 billion light years is far too small to be the right answer. In actuality, we can see for 46 billion light years in all directions, for a total diameter of 92 billion light years.