This might be a dumb question, but WHAT is expanding? I think it is all the other stars / suns are moviving away from us? But we keep a relatively similar distance to our own sun and the other plants?

I would rather live my life as if there is a God and die to find out there isn't, than to live my life as if there isn't and die to find out there is.

The expansion of the universe is accelerating, contrary to what used to be thought. This gave birth to what is now called "dark energy", an unknown energy which sustains this acceleration.

It is said human beings are complex. I say it's a complex challenge to be a human.

No, there's nothing special about us. It's the whole universe that is expanding. The typical analogy is with a baloon with dots on it that represent the galaxies. As you blow into the baloon it expands, and the dots expand with it, though there's not one center around which the expansion occurs.

It is said human beings are complex. I say it's a complex challenge to be a human.

Our solar system contains the sun, planets, moons, asteroids and comets. A galaxy contains the stars, like our sun, and the afore mentioned material as well as dust, gases, black holes and some unique stuff called dark matter. Our galaxy, the Milky Way, contains 200 to 400 billion stars. It is the galaxies that are moving away from each other. Our galaxy is moving away from other galaxies at about 600 km per second. The distant galaxies appear to be accelerating even faster up to 1000 km per second.

Given the size of our galaxy, and it is not a big one some are up to a trillion star, multiply it by the estimate of 100 billion galaxies to get an idea of how many stars are out there.

The gravitational pull of the sun’s gravity is very close to us and it keeps us in orbit. Our solar system acts like a family and we all stay in relative place in the bigger mass of the Milky Way. The distance between the galaxies is great so the gravitational pull is weak. Gravity works on the inverse square formula or: 1 divided by the distance times distance. Light uses the same formula.

If you have a light bulb and you measure its brightness at one meter and compare it to ten meters, it is a hundredth as bright at ten meters.

This is a simplified annotated explanation.

"Those who can make you believe absurdities can make you commit atrocities."-Voltaire
When one person suffers from a delusion, it is called insanity. When many people suffer from a delusion it is called religion. Robert M. Pirsig Evolve!

@Anicka... thanks, but I wasn't meaning to say that we are special..... So, is it correct then that the sunand planets and everything in space is moving further from each other?

I would rather live my life as if there is a God and die to find out there isn't, than to live my life as if there isn't and die to find out there is.

@longload. It's the galaxies which are moving further from each other, not the solar systems. The matter inside galaxies keeps the stars in them from moving away, through its gravitational pull, and the gravity of the stars keep their planets orbiting around them.

It is said human beings are complex. I say it's a complex challenge to be a human.

VBC555- So, we are remaining relatively close to the same distance all the time to our sun and planets? (i do understand our distance from the sun varies with our orbit)

I would rather live my life as if there is a God and die to find out there isn't, than to live my life as if there isn't and die to find out there is.

@Anicka - ok thanks... I think I get it now

I would rather live my life as if there is a God and die to find out there isn't, than to live my life as if there isn't and die to find out there is.

@longload. You're welcome

It is said human beings are complex. I say it's a complex challenge to be a human.

I dont think the scientists are sure about it,some say it is expanding some say on the contrary it will diminish.

Check out CBS's 'Stephen Hawkings Univers' series. You'll get the answers to the expansion question.

sorry it's PBS not CBS.

Longload"Our orbit round the sun is not a perfect cirle so yes there are variations ,think elliptical....

Well i saw in a documentary that it is not only expanding. Sometime in the future according to the scientists its gonna contract and become one big thing again, like the one producing the big bang. What a cool question, i'm gonna find out

Little to the left.

Thing is that they only think they know. or they don't know. There seem to be many theories on it.
Whatever... the universe is unlikely to come to its end tomorrow. Possibly in a few zillion years, but I don't think I'll be around then. And if I am, then I hope I have my camera with me.

Daar is de lente, daar is de zon bijna, maar ik denk dat ze weldra zal komen. De fallus impudicus staat al in bloei En de blaadjes krijgen bomen. M'n vrouw en m'n kat zijn allebei krols en de klokken vertrekken naar Rome

I’m sure I’ll loose much needed sleep agonising over the cosmos, its all relative to me anyway…..

"Save a child use a condom"

Further questions.... Does this expanding universe have its begginning with the big bang? Did matter, time and energy already exist? And how can we determine when this happened? or, can we determine that if we don't know where the furthest gallery is?

I would rather live my life as if there is a God and die to find out there isn't, than to live my life as if there isn't and die to find out there is.

Yes, the expanding universe was born with the big bang. At the beginning it was all energy, but as the universe expanded and cooled, particles, matter and forces took shape. Time is one of the dimensions of this universe. It happened about 13 billion years ago.

It is said human beings are complex. I say it's a complex challenge to be a human.

I'm being lazy...I likely could look this info up easy enough... But I'm just trying to figure, is 13 billion years enough? I'm trying to rationalize that with 555's answer above regarding the size aqnd vastness

I would rather live my life as if there is a God and die to find out there isn't, than to live my life as if there isn't and die to find out there is.

Yes, about 13 bilion years old (betwen 13 and 14) is the age of the universe.

It is said human beings are complex. I say it's a complex challenge to be a human.

Amazing!

Well i think at the beginning there was energy and matter, time...we invented the time.

Little to the left.

Time is one of the four dimensions in which we exist, along with the three dimensions of space (though apparently not the only ones in the universe, according to the String Theory). We invented a way of measuring it, based on the Earth's motions, but it exists by itself.

It is said human beings are complex. I say it's a complex challenge to be a human.