Originally posted by Weatherlawyer:
Theories just get in the way of facts most of the time.
Perhaps that is the only important thing I have learned in all this?
Originally posted by JPL Pasadena California:
Seeing is believing, except when you don't believe what you see.
Hubble found an arc of light behind an extremely massive cluster of galaxies 10, 000,000,000 light-years away. Observed as it existed when the universe was roughly a quarter of its current age of 13.7 billion years.
At that epoch there are not enough galaxies behind the cluster bright enough to be seen even if they were 'lensed,' or distorted by the cluster. Galaxy clusters become less massive the further back in time you go.
Astronomers frequently study galaxy clusters to look for faraway, magnified galaxies behind them that would otherwise be too dim to see with telescopes. Many such gravitationally lensed galaxies have been found behind galaxy clusters closer to Earth.
The cluster is the most massive found at that epoch, weighing as much as 500 trillion suns, 5 to 10 times larger than other clusters found at such an early time in the history of the universe.
Finding this ancient gravitational arc may yield insight into how, during the first moments after the Big Bang, conditions were set up for the growth of hefty clusters in the early universe. Analysis revealed that the lensed object is a star-forming galaxy that existed 10 billion to 13 billion years ago.
Distorted by gravitational lensing:
Now for the facts.
The Hubble telescope was named after an astronomer who proposed you could tell the distance of stars by something called the red shift. They are too far way to be measured the way we measure planets.
So they are in effect being measured by a theory. I am not going to try explaining a mere theory.
When they say it is so many billions of miles away and that means it was formed at so and so a time before the big bang, that is a theory about a theory built onto a theory.
1. That series of theories starts on a supposition that is far more unbelievable than miracles. Before there was anything there was nothing then it all started by magic and was ordered out of chaos by accident.
2. And ever since then it has been expanding to infinity which infinite distance we know within the margins of out theories. (In theory.)
3. We look at the stars and see something that was only there light years ago. Since they were there they have moved on.
That's a bit like watching live TV. You see the image the camera saw milliseconds ago because it took time to send the image to your TV set.
Another analogy is watching someone hitting a board or a bell or some such thing away off in the distance. Because they are down the other end of the street, the sound doesn't reach you at the same time that you see the action.
Now imagine the delay involved if the action took place millions of light years ago. A light year is the distance light will travel in 1 year.
The nearest star is 4 light years away. So by the time you see it it has moved god knows how far away.
I am not going to argue that one. None the less it remains a theory, even though it has been studied since Grecian/Roman times. It has to remain a theory because nobody has described a scientific control on any of the research, mathematical or empiric.
All we know is that the stars move about 70 moments of arc in a lifetime; or 1 per year. That is, if I remember correctly. When the Pyramids were built, the Pole Star was Thuban in El Draco. (Again IIRC.)
What is actually happening, we don't know for sure. Just bear that in mind when you choose your beliefs.