No. While astronomers do believe that the universe has been expanding since the Big Bang, this expansion works on the largest of scales, the scale of the galaxies. In other words, our solar system – our sun and its family of nine planets – is not expanding.
Earth is located 150 million kilometers – about 93 million miles – or 8 light-minutes from the sun. It’s thought to have been located at this distance from the sun since our solar system was born, some four-and-a-half billion years ago. So the sun isn’t getting farther from Earth. And, likewise, our sun isn’t getting farther from other stars in our own galaxy.
Why don’t the solar system and galaxy expand, while the universe as a whole does? The solar system and galaxy are held together gravitationally. Our Milky Way galaxy is a collection of hundreds of billions of stars. It’s thought to be one of billions of galaxies in the universe.
Now we’re at the scale that astronomers talk about when they speak of the “expanding universe.” Our galaxy is getting farther from other galaxies – every galaxy is. There are billions of galaxies, and they are all moving away from each other. In that sense, the universe is thought to be expanding.
Fine. I want to know why moon is always showing its same face to the earth?
we don’t always… during a new moon we see the other side of the moon and its like completely dark so it’s not really…
It’s because the rotational period of the moon is the same as its orbital period. It takes the same time for the moon to rotate as it does to revolve around the Earth. Therefore, by the time it has made a full rotaion it is already beginning its next orbital cycle.
A question over your notes: “How can expand the Universe equal in all point and subtract the mass zones as say the theories? How can compute this if for example milky way has 100.000 light years in size?”
I’m against Universe expansion:
For example a question: – The universe expand in any radius at light speed: How can accelerate? At what speed expand the diameter (radius x 2)?
This and more questions, doubts, proofs and hypothesis agains Universe expansion in http://bigbangno.wordpress.com
Thanks.