how big is the universe?

Answer 1

Infinite. Working on the assumption that any boundary must have something beyond it.

Answer 2

The Universe is made up of millions of galaxies. Also out in space is background radiation from all the explosions and nuclear fusion going on within stars and nebulae. And, of course, the universe has a whole lot of empty space.

In fact, there is so much space even between single stars in a galaxy that it is difficult to measure in miles or kilometers. Scientists use a distance measurement in space that is expressed as the distance light will travel in the course of a year - a light year. Light travels at a speed of about 186,000 miles per second. That means that light can travel 7.5 times around the entire world in just 1 second! In a year's time, light can travel six trillion miles (6,000,000,000,000). It takes over 4 years for the light from the nearest star to reach the Earth.

Answer 3

a few interesting answers came in...

The Universe at this time has been stated to be
40 Billion Light Years in all directions from Earth.
That is the fartherest distance we can "see" with
our present level of optical and radio telescope
equipment. That is not the end of space, that is
just as far as we can see with our equipment.

Infinite? I don't know. Nobody knows that, it is just
a theory. However, 40 Billion Light Years is such
a big, big distance that it might as well be infinity.
Nobody will ever travel out there and be able to tell
"us" about it. Travel would take way more than
40 Billion Years and we will all be dead by then.

Answer 4

In Big Bang cosmology, the observable universe (also called the Hubble Volume) is the region of space bounded by a sphere, centred on the observer, that is small enough that we might observe objects in it, i.e. there has been sufficient time for light emitted by an object to arrive at the observer. Every position has its own observable universe which may or may not overlap with the one centered around the Earth.

The word observable used in this sense has nothing to do with whether modern technology actually permits us to detect radiation from an object in this region. It simply means that it is possible for light or other radiation from the object to reach an observer on earth. In practice, we can only observe objects as far as the surface of last scattering, when the universe became transparent. However, it may be possible to infer information from before this time through the detection of gravitational waves.

[edit] Size
The comoving distance from the Earth to the edge of the visible universe is about 46.5 billion light-years in any direction; this is the comoving radius of the visible universe. It is sometimes quoted as a diameter of 92-94 billion light-years[3]. Since the visible universe is a perfect sphere and space is roughly flat, this size corresponds to a comoving volume of about

Answer 5

Though the Universe appears immense ,the actual mass content volume is suprisingly small. Based on the calculated mass of the Universe,and if all the space was removed between all atoms and particle so that al masses would touch ,it would form a volume of 2 cubic meters.
Of course Big Bang theory exagerated a litte they calculated it to be the size of a Golf ball. Quantron theory is not in agreement with that. The 2 cubic meter calculation is more realistic.

Answer 6

The search from Cosmology and Vedas that interlinks Science of Philosophy. The Universe is projected to be
10^9- !0^10 Light Years that interlinks Cosmos Yoga
Cosmic Pot Energy of the Universe-Space Science and Technology Institute-STSCI-Symposium. May 2003 by V.Nanduri and books by Vidyardhi Nanduri give more details
Plasma Vision of the Universe : http://www.buymyebook.com/buy/authorinfo.asp?EbookId=195

Cosmic to PREM -Plasma Regulated Electro-Magnetic Universe : http://www.buymyebook.com/buy/authorinfo.asp?EbookId=228

Answer 7

If the "universe" is our definition for "everything that is out there" then I will quote the Roman philosopher Lucretius who said:

"The universe is infinite. What else can it be?"
Because there surely has to be SOMETHING outside whatever edge we find. And this must be counted itself as being part of the "universe". And so on for ever.

But another perspective is that space-time itself may be curved so has no edges without being infinite in size, so that as you go in what you think is a straight line you'll end up back where you started. And if you go in a curved line you'll hmm I don't know that one.

Personally I think we are in a giant cathode ray tube of god's television set.

Answer 8

If we talk about a 4D space-time, the universe is like the 3D surface of a 4D ball. There will be no boundary in the way we know in everyday means to measure the size of the universe in 3D way of thinking.
Yet although the universe is about 40 billion light years as someone have stated above me, it doesnt meant that it have no boundary nearby.
Black holes are the boundary between this universe and the others universes. Inside a black hole Schwarzchild Radius the curvature of space-time is infinite, and the predictabilty of our law of physic break down. The region inside a black hole Schwarzchild Radius is in essence another universe.
So our universe is finite, have no boundary like in every day sense, but it does have black holes as its boundary with other universes.

Answer 9

It can't be infinite 'cos scientists tell us that is was created during the big bang and expanded afterwards, so it started small and now it's really really big, but it can't be infinite. Whats outside it though is another question. Scientists are not sure but can only tell us that is must be a really boring place.

Answer 10

It is infinitely expanding. What we know is it is unapplicable to know the size of the universe. The universe may have no edge.

Answer 11

My Universe is as big as the Earth, because i ain't ever going any further than that in my lifetime!
Good Q though!