If by space you mean the known Universe, then it is about 93 billion light-years from end to end.

One light-year is the distance that light travels in 1 year – this is about 9.5 trillion km. So the Universe is about 880 thousand billion billion km – an astronomically huge number!

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How is this determined? When light can be slowed and or sped up in a laboratory then the universe must have the potential to do the same depending on where this light would be travelling. We know gravity will bend light so, is this 93 billion light-years a number based on a straight line from end to end with no distortion calculated?

Photons can not be “sped up” but you are correct that they can be slowed down. Light can’t go faster than the universal constant of about 186,000 miles per second. That’s the speed of light. It can’t go any fast than that. Also, the universe doesn’t really slow light down, just bend it and the added/shortened distance that may occur doesn’t add or subtract much to that measurement.

Search on the internet for “speeding up the speed of light” and you’ll find links to support my comment.

What is “the end” then ???

it is infinite

How can a fourteen billion year old universe expanded to 93 billion light years,it would have to expand faster than the speed of light.

Good point! Apparently it does expand faster than light.

How can the universe expand 93 billion light years in 14 billion years.

If the universe were expanding at the speed of light to 93 billion light years it would be 46.5 billion years old ,its going slower it should be older.I heard scientists looked at universe and guessed the age what did they look at ?

Even though matter cannot move faster than c (the speed of light), spacetime itself can. Nothing stops spacetime from expanding (or contracting) at a speed faster than c – this is absolutely permissible by the laws of physics. Now, given this possibility, it can happen that in a period of 14 billion years or so (the age of the Universe), spacetime has expanded to cover a distance of more than 14 billion lightyears. What we’ve been able to determine is that our current observable Universe has expanded to a distance of about 93 billion lightyears “from end to end”. I have these in quotes simply because there are no physical edges to our Universe – at least none that we know of.

The rapid expansion of the early Universe (called the Inflation phase) is what caused the Universe to be a size larger than what we would expect had it expanded at the speed of light. What has caused this expansion is an energy which is as yet to be completely understood and described by our current framework of physical laws and models. In the interim, we have termed this energy ‘Dark Energy’.

We have to be careful in terms of how we conceive this expansion of spacetime, particularly in terms of distances. It is not so much that things are moving away from each other at a speed greater than c. It’s not like we are all moving faster than c, away from one another. It is easy to misinterpret this expansion of spacetime as an increasing separation between bodies (stars and galaxies, etc.) in the Universe. There are no analogies simple enough to describe it without falling prey to the wrong interpretation. Perhaps the way to understand it is in terms of a certain property of spacetime which has to do with how distances are measured. It is this property of spacetime which is changing, thus causing distances we measure (or calculate) to be the value they are. This property of spacetime is not constant but can change (indeed increase at a speed greater than c) thus allowing our Universe to be 93 billion lightyears in size even it is only about 14 billion years old.