Can anyone answer my question about 14 billion light years away?
Even if we can travel near the speed of light, how can we map how far that is? Some of the claims that something is billions of light years away is ridiculous. What if the sun or planet we are looking at disappears? Let's make it more reasonable like 1 light year away. Then we can map the planet and be able to travel there near light speed in a little over a year's time. However, there would be a point where we could not depend on what we saw today. Is that 10 light years? Is it 50 light years? Is it 100 light years? Due to space changing and time being dilated, we would not be able to get from here to there.
Thus, can we trust when astrophysicists say something is 14 billion light years away? They sound like they are lying.
The speed of light is 186,282 miles per second. It is considered a constant - hence c in E=Mc^2.
A light year is the distance light travels in one year: about 6 trillion miles. More exactly [from Wikipedia): 5.88 trillion
miles (5.88 x 10^12 mi).
Dating the furthest galaxies is more complex - one method involves a red shift in the light spectrum for various elements producing the light. I will start with our literature on a different red shift also applicable to your question: [gravitational red shift]
This is an authorized Web site of Jehovah’s Witnesses. It is a research tool for publications in various languages produced by Jehovah’s Witnesses.
wol.jw.org
"In 1916 Albert Einstein put forward his general theory of relativity. His amazing discovery was that gravity not only shapes the universe but also governs the way we see and measure it. Why, gravity even affects the way time is measured!
Again, an illustration helps clarify matters. Imagine space to be like a boundless rubber sheet. Now, placing an object on this flexible mat will cause a dimple, or depression. According to Einstein’s description, the earth, the sun, and the stars are like objects on a flexible mat, causing space to curve. If you roll another object onto the rubber sheet, it will be deflected into a curved path by the depressed area around the first object.
Similarly, the earth, the planets, and the stars move along curved paths, following the natural “depressions” in space. Even a beam of light is deflected when passing near massive objects in the universe. Furthermore, Einstein’s equations predicted that light traveling against gravity would lose some of its energy, as noted by a slight shift in color toward the red end of the spectrum. Physicists call this phenomenon gravitational redshift."
More detail is here:
Mössbauer effect - Nuclear, Spectroscopy, Physics: Mössbauer’s discovery has had far-reaching consequences because it has made available electromagnetic radiation (gamma rays) whose frequency is more precisely defined than any other known to date and has provided a new technique for measuring...
www.britannica.com
Red shift due to speed - also a doppler effect/shift:
This is an authorized Web site of Jehovah’s Witnesses. It is a research tool for publications in various languages produced by Jehovah’s Witnesses.
wol.jw.org
"Astronomer Edwin Hubble (1889-1953) realized that a red shift in light from distant galaxies showed that our universe is expanding and thus had a beginning "
Then, too, there is quasar speed. All galaxies are believed to be rushing away from one another at fantastic speeds. But some quasars are thought to be moving away at even greater speeds. They are usually considered to be the farthest material thing from the earth, maybe even twelve billion light-years away. How are such estimates made?
On the basis of what is called “red shift.” Light appears to travel in a wave-like pattern. As it passes through a prism, longer waves produce a deep-red color; the shorter ones are bluish. The process of “red shift” maybe illustrated with a train whistle. As a train approaches you (causing the sound waves to shorten), the whistle’s pitch seems to rise. However, after passing (and as the sound waves lengthen), the pitch drops. Light waves behave in a similar way. According to the “red shift” rule, objects leaving the earth have a longer wave length and so produce an increased amount of red shift. On this basis, quasars are thought to be the most distant objects in the universe. But there is still more to the quasar mystery.
To some experts, they imply contradictions to Einstein’s theory, on which most views of the universe are based. His theory says that nothing in the universe can travel faster than the speed of light. Yet some scientists claim to have found that parts of one quasar are traveling away from each other at
ten times the speed of light!
Rather than say that Einstein is wrong, many now argue that it is the red-shift rule that is in error. One argument says that quasars are really closer than they appear and that their red shift results from ‘spectral tricks.’ Another claims that the weight of quasar material has changed through millions of years, giving a misleading red-shift impression. Nevertheless, a few astronomers are willing to accept the possibility that Einstein’s theory, if not wrong, is incomplete."
More detail here:
Quasar - Discovery, Light, Galaxies: Although the first quasars known were discovered as radio sources, it was quickly realized that quasars could be found more efficiently by looking for objects bluer than normal stars. This can be done with relatively high efficiency by photographing large...
www.britannica.com
Excerpt:
" The combination of high luminosities and small sizes was sufficiently unpalatable to some astronomers that
alternative explanations were posited that did not require the quasars to be at the large distances implied by their redshifts. These alternative interpretations have been discredited, although a few adherents remain. For most astronomers, the
redshift controversy was settled definitively in the early 1980s when American astronomer Todd Boroson and Canadian American astronomer John Beverly Oke showed that the fuzzy halos surrounding some quasars are actually starlight from the galaxy hosting the quasar and that these galaxies are at high redshifts."
New method correlates redshift of different quasars
physicsworld.com
The whole 2012 article is of interest - here is a portion:
"Astronomers are always keen to find new and accurate methods to measure cosmic distances and the expansion of the universe. “Standard candles” such as Cephids and supernovae have played important roles in astronomy. Indeed, the discovery of the accelerating expansion of the universe through observations of distant supernovae won Saul Perlmutter, Adam Riess and Brian Schmidt the 2011 Nobel Prize for Physics. But using supernovae to gauge the extreme distances of the universe has its problems – the furthest known supernova is at a redshift of about 1.7 and so reliable measurements of distances greater than that are not possible using supernovae. Also, astronomers have to wait for stars to “go supernova” and then have a short window of time to make their observations.
Contrary to that, the furthest quasar has been found at a redshift of about 7.1, and so looks much further back to the beginnings of the universe. Also, quasars are some of the brightest objects in the universe, and unlike supernovae can be studied for much longer time scales. Unfortunately, quasars emit different amounts of light in all wavelengths, and this makes it very difficult to use them to measure cosmological distances using their luminosity–distance relation. It was only last year that another team of researchers showed that it was possible to use the luminosity–radius relation of active galactic nuclei – a type of quasar – to determine their distance; using them as standard candles."
See the article for more detail.
On the lighter side a definition of standard candles:
A red standard candle is about 9 inches high and tapered from 1 inch in diameter at base to .25 inches at top - there generally are strings attached - though these are not wick - ed.
The height of a standard candle decreases in proportion to the heat and light they produce - this is called the candle effect. This decrease stops as the candle waxes cold.
