Is that right?
So u have a BIG knowledge about it.
If anybody would ask u about a fantastic story of astronomy what one u would take to tell???
I am simply inquisitive
Tell us a tale Coco!
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Marwin
- Posts: 1252
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Tell us a tale Coco!
U were study astronomy, and u absolved this with distinction/full marks.
Is that right?
So u have a BIG knowledge about it.
If anybody would ask u about a fantastic story of astronomy what one u would take to tell???
I am simply inquisitive
Is that right?
So u have a BIG knowledge about it.
If anybody would ask u about a fantastic story of astronomy what one u would take to tell???
I am simply inquisitive
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}TCP{Viper//
- Posts: 1412
- Joined: Tue Aug 31, 2004 10:23 pm
- Location: netherlands
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}TCP{Ramses
- Posts: 3754
- Joined: Sun Feb 02, 2003 12:09 am
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partydevil
Ok, two questions here, so I'm first gonna answer the one from Marwin/partydevil and then the one from Ramses.
Right after the Big Bang, the whole (small) universe only consisted of pure energy. It expanded rapidly and thereby created (or better: defined) space. However, the density of radiation was so high that the existance of atoms was impossible. Moreover, matter and anti-matter were created alike. Both destroyed each other, transforming themselves into energy again. It is one of the big questions of today, why a small portion of matter remained in the end.
However, about 10 seconds after the Big Bang, protons and neutrons connected to form the first Hydrogen, Deuterium, Helium and Lithium cores. The abundances roughly were 75% Hydrogen, 25% Helium, 0.001% Deuterium and very little Lithium. This was the so called phase of primordial nucleosynthesis. The remaining neutrons dissolved into protons and electrons during the following 5 minutes.
So the Big Bang created no other elements than these simplest ones: Hydrogen cores just have 1 proton. Deuterium is "heavy Hydrogen", i.e. Hydrogen with an additional neutron. Helium got 2 protons and 2 neutrons and Lithium consists of 3 protons and 4 neutrons.
All "higher" elements were produced by stars later on. For example, the fusion processes in the core of our Sun create Helium from Hydrogen. More massive stars can fuse Helium atoms and thus create Beryllium and Carbon. Even more massive stars can fuse Carbon, and so on. The "highest" element stars can produce by fusion of Silicon is Iron (atomic number 26). The fusion reactions beyond that barrier are exothermal and the required temperatures would exceed 30 billion degrees Celsius by far.
Elements with even higher atomic numbers (like Copper, Silver, Gold, Lead and all the others) are produced by supernovae of type II only. These supernovae are explosions of stars with a mass of 8 solar masses and above. Such an explosion releases unbelievably high energies (in the range of 10 to the power of 51 erg). The energy compresses the atoms and thus leads to fusion of the "higher" elements. At the same time, all elements created by the star are scattered through the surrounding space.
Stars form from cold molecular clouds. These days, such clouds almost always are remnants of stars that exploded millions or even billions of years ago. Observed stars are divided into so called populations. Population III stars were the first stars that have formed and these naturally consist of no higher elements. Population II stars formed billions of years after these and contain the higher elements created by the population III stars. The youngest stars (like our Sun, which is an intermediate population I star) have a high abundance of these higher elements. Scientists generally call the abundance of elements other than Hydrogen and Helium metallicity.
Now since the Sun and its planets have formed from the remnants of older stars and no other elements than mainly Hydrogen and Helium were created during the Big Bang, this means that all atoms in your bodies (except these two) were created by fusion in the core of a no longer existing star or in a supernova explosion. Thrilling thought, isn't it?
Now about Ramses' question:
Light naturally travels with the speed of light (which approximately is 300000 kilometers per second). So whenever we observe something in space, we have to consider that the light emitted by the observed object has to travel the distance to Earth. Even if light is extremely fast (in fact, nothing is faster at all), it can't travel faster than that. For example, the Moon has an avaerage distance of 384000 km. This means that the image of the Moon that we see in the sky is somewhat older than 1 second when we see it. The distance of the Sun is about 150 million km, so the light of the Sun that we see on Earth has travelled 8 1/2 minutes before it reaches our eyes. If for some reason the Sun would explode now, we wouldn't know anything about it in the following 8 minutes.
For higher distances, the delay increases more and more. For example, the star closest to our Sun is Alpha Centauri and is 4.22 light years distant. A light year is the distance that light can travel within a year (i.e. the amount of seconds in a year, multiplied by 300000). It equals a distance of 9.46 quadrillion kilometers. So the distance to Alpha Centauri is approximately 40 quadrillion kilometers. Light travels that distance within 4.22 years, which is why the image of Alpha Centauri that we see on Earth is more than 4 years old. That means that the state of Alpha Centauri we currently observe is from a time when I wasn't a member of this clan.
When we look around ourselves in space, we find that everything we see disappears from us. Basically, we can assume ourselves to be somewhere between the center of the initial Big Bang and the border of the universe. The universe still expands and the outer border moves away from the center with approximately the speed of light. The space inbetween is being stretched at the same time. Imagine you have a balloon with no air in it yet. If you draw small black dots on the surface, you can see each dot disappear from each other when filling it with air. It's the same in our universe, just in three dimensions.
The expansion of the univserse was discovered by Edwin Hubble in 1929. The determination of the expansion rate (called Hubble constant) is a subject of ongoing investigation until today. Recent observations claim a value of about 69.7 kilometers per second per megaparsec. This means that an object with a distance of one megaparsec (equals 3.26 lightyears) disappears with a speed of 69.7 km per second. Farther objects disappear even faster. It's just like with the dots on the ballon: The distance between more distant pairs grows faster than between nearer pairs.
Due to the fact that space itself is being stretched, this also means that the waves of light are being stretched. Therefore, light from distant places is more stretched than that of nearer places when it reaches Earth. Since light with longer wavelengths is nearer to red than that of shorter wavelengths, astronomers say light is being red shifted. Thus the amount of the shift in fact is an indicator for the distance of the observed object.
Anyway, to answer Ramses' question: Since no object disappears faster than the speed of light, we're able to see the light of even the farthest objects. In fact, the most distant object observed till today has a redshift value of 8.2, which means that its light was emitted only 600 million years after the Big Bang. Or in other terms: Since the universe is said to have a radius of 13.7 billion light years, that object would be 13.1 billion light years distant.
Right after the Big Bang, the whole (small) universe only consisted of pure energy. It expanded rapidly and thereby created (or better: defined) space. However, the density of radiation was so high that the existance of atoms was impossible. Moreover, matter and anti-matter were created alike. Both destroyed each other, transforming themselves into energy again. It is one of the big questions of today, why a small portion of matter remained in the end.
However, about 10 seconds after the Big Bang, protons and neutrons connected to form the first Hydrogen, Deuterium, Helium and Lithium cores. The abundances roughly were 75% Hydrogen, 25% Helium, 0.001% Deuterium and very little Lithium. This was the so called phase of primordial nucleosynthesis. The remaining neutrons dissolved into protons and electrons during the following 5 minutes.
So the Big Bang created no other elements than these simplest ones: Hydrogen cores just have 1 proton. Deuterium is "heavy Hydrogen", i.e. Hydrogen with an additional neutron. Helium got 2 protons and 2 neutrons and Lithium consists of 3 protons and 4 neutrons.
All "higher" elements were produced by stars later on. For example, the fusion processes in the core of our Sun create Helium from Hydrogen. More massive stars can fuse Helium atoms and thus create Beryllium and Carbon. Even more massive stars can fuse Carbon, and so on. The "highest" element stars can produce by fusion of Silicon is Iron (atomic number 26). The fusion reactions beyond that barrier are exothermal and the required temperatures would exceed 30 billion degrees Celsius by far.
Elements with even higher atomic numbers (like Copper, Silver, Gold, Lead and all the others) are produced by supernovae of type II only. These supernovae are explosions of stars with a mass of 8 solar masses and above. Such an explosion releases unbelievably high energies (in the range of 10 to the power of 51 erg). The energy compresses the atoms and thus leads to fusion of the "higher" elements. At the same time, all elements created by the star are scattered through the surrounding space.
Stars form from cold molecular clouds. These days, such clouds almost always are remnants of stars that exploded millions or even billions of years ago. Observed stars are divided into so called populations. Population III stars were the first stars that have formed and these naturally consist of no higher elements. Population II stars formed billions of years after these and contain the higher elements created by the population III stars. The youngest stars (like our Sun, which is an intermediate population I star) have a high abundance of these higher elements. Scientists generally call the abundance of elements other than Hydrogen and Helium metallicity.
Now since the Sun and its planets have formed from the remnants of older stars and no other elements than mainly Hydrogen and Helium were created during the Big Bang, this means that all atoms in your bodies (except these two) were created by fusion in the core of a no longer existing star or in a supernova explosion. Thrilling thought, isn't it?
Now about Ramses' question:
Light naturally travels with the speed of light (which approximately is 300000 kilometers per second). So whenever we observe something in space, we have to consider that the light emitted by the observed object has to travel the distance to Earth. Even if light is extremely fast (in fact, nothing is faster at all), it can't travel faster than that. For example, the Moon has an avaerage distance of 384000 km. This means that the image of the Moon that we see in the sky is somewhat older than 1 second when we see it. The distance of the Sun is about 150 million km, so the light of the Sun that we see on Earth has travelled 8 1/2 minutes before it reaches our eyes. If for some reason the Sun would explode now, we wouldn't know anything about it in the following 8 minutes.
For higher distances, the delay increases more and more. For example, the star closest to our Sun is Alpha Centauri and is 4.22 light years distant. A light year is the distance that light can travel within a year (i.e. the amount of seconds in a year, multiplied by 300000). It equals a distance of 9.46 quadrillion kilometers. So the distance to Alpha Centauri is approximately 40 quadrillion kilometers. Light travels that distance within 4.22 years, which is why the image of Alpha Centauri that we see on Earth is more than 4 years old. That means that the state of Alpha Centauri we currently observe is from a time when I wasn't a member of this clan.
When we look around ourselves in space, we find that everything we see disappears from us. Basically, we can assume ourselves to be somewhere between the center of the initial Big Bang and the border of the universe. The universe still expands and the outer border moves away from the center with approximately the speed of light. The space inbetween is being stretched at the same time. Imagine you have a balloon with no air in it yet. If you draw small black dots on the surface, you can see each dot disappear from each other when filling it with air. It's the same in our universe, just in three dimensions.
The expansion of the univserse was discovered by Edwin Hubble in 1929. The determination of the expansion rate (called Hubble constant) is a subject of ongoing investigation until today. Recent observations claim a value of about 69.7 kilometers per second per megaparsec. This means that an object with a distance of one megaparsec (equals 3.26 lightyears) disappears with a speed of 69.7 km per second. Farther objects disappear even faster. It's just like with the dots on the ballon: The distance between more distant pairs grows faster than between nearer pairs.
Due to the fact that space itself is being stretched, this also means that the waves of light are being stretched. Therefore, light from distant places is more stretched than that of nearer places when it reaches Earth. Since light with longer wavelengths is nearer to red than that of shorter wavelengths, astronomers say light is being red shifted. Thus the amount of the shift in fact is an indicator for the distance of the observed object.
Anyway, to answer Ramses' question: Since no object disappears faster than the speed of light, we're able to see the light of even the farthest objects. In fact, the most distant object observed till today has a redshift value of 8.2, which means that its light was emitted only 600 million years after the Big Bang. Or in other terms: Since the universe is said to have a radius of 13.7 billion light years, that object would be 13.1 billion light years distant.
Tbh bing bang is just nonsence tho, its funny how pride and denial comes into science.
Remember i saw a documentary once too where a research about how many scientist belived in big bang etc, was just 55%. (about 5yrs old). And then also ppl who has been threated by their lives cause of their research to disapprove big bang.
Anyway i dont wanna offend coco tho, but if u manage to explain.
Quasar+
Red shift+
Inflation = A universe where big bang happend?.
I would be insanly impressed if u manage to clearify how this is possible with a so called big bang universe.
Googled a little bit too, think i found a link who can explain it way better then me.
http://nov55.com/bb.html
Me still loves u anyhow tho ^^
Remember i saw a documentary once too where a research about how many scientist belived in big bang etc, was just 55%. (about 5yrs old). And then also ppl who has been threated by their lives cause of their research to disapprove big bang.
Anyway i dont wanna offend coco tho, but if u manage to explain.
Quasar+
Red shift+
Inflation = A universe where big bang happend?.
I would be insanly impressed if u manage to clearify how this is possible with a so called big bang universe.
Googled a little bit too, think i found a link who can explain it way better then me.
http://nov55.com/bb.html
Me still loves u anyhow tho ^^
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Your weirdness has been posted.
Your weirdness has been posted.
Oh my god, Ronny, where did you get that from? Pride and denial? Scientists don't deny facts. When facts say something different, a theory is proven wrong - very easy. People's life threatened cause they don't support the Big Bang theory? Whoever said that must have read too many cheap SciFi novels. 
That text you posted is completely unscientific. Did you notice that there are no arguments in it? The guy who wrote is just says everything science claims is wrong. But he doesn't give reasons and he also doesn't say what's right in his view. Most likely because it would be easy to disprove. If he could really prove that the Big Bang theory is wrong, nobody would believe in that theory anymore.
It's easy to say that just 55% of the scientists support the Big Bang theory. Where does that number come from? It's useless without a reliable source. And even if it was true, that would mean that still the majority of experts favour it.
What's so hard about explaining red shift? I already did that above. Quasars are the cores of galaxies emitting powerful radiation in the radio wavelength. And don't mix up expansion with inflation. The early universe had an inflationary phase in which it grew exponentially. However, this is just a theory (what else could it be?) that can explain most of the things we can observe today. Still, there's no better explanation.
That text you posted is completely unscientific. Did you notice that there are no arguments in it? The guy who wrote is just says everything science claims is wrong. But he doesn't give reasons and he also doesn't say what's right in his view. Most likely because it would be easy to disprove. If he could really prove that the Big Bang theory is wrong, nobody would believe in that theory anymore.
It's easy to say that just 55% of the scientists support the Big Bang theory. Where does that number come from? It's useless without a reliable source. And even if it was true, that would mean that still the majority of experts favour it.
What's so hard about explaining red shift? I already did that above. Quasars are the cores of galaxies emitting powerful radiation in the radio wavelength. And don't mix up expansion with inflation. The early universe had an inflationary phase in which it grew exponentially. However, this is just a theory (what else could it be?) that can explain most of the things we can observe today. Still, there's no better explanation.
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partydevil
beside that it gives a explanation on how it could have been started}TCP{Coco wrote: What's so hard about explaining red shift? I already did that above. Quasars are the cores of galaxies emitting powerful radiation in the radio wavelength. And don't mix up expansion with inflation. The early universe had an inflationary phase in which it grew exponentially. However, this is just a theory (what else could it be?) that can explain most of the things we can observe today. Still, there's no better explanation.
the big bang theory is still a theory, or are their rly facts that it rly happand?
if it happand how could in nothing start anything?
and if there rly was nothing befor the big bang, then is it possible that another big bang can happen in the nothingness outside this univers?
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}TCP{Ramses
- Posts: 3754
- Joined: Sun Feb 02, 2003 12:09 am
Cheers Coco, but it's still hard to visualise for me.
What direction is that star from us in relation to big bang ground zero ? At 600 million years after the bang .... if that star was on the opposite side of the bang to us then at most we could have been an equivalent 1.2 billion years away from each other when the light left it (I guess, if we were travelling in opposite directions) ... so why has it taken 13.1 billion years to reach us 
. Surely we can't be accelerating away so fast ... but I'd have to get a calculator and convert to miles with light speed and those megaparsecs etc to work it all out 
Another thing I'm not sure of is ... why doesn't the Universe have a hollow centre (or does it) ? I'm guessing objects are moving away from the big bang ground zero at different rates, but even so I suppose some objects trajectories have been changed due to gravity/orbital pull, maybe some have done a 180 .
BTW This is just my poor battered imagination trying to grasp/make sense of things and filling in the gaps from tv documentaries etc I'm not casting doubt on the big bang theory or any variation; the scientists would do that themselves if/as soon as it didn't fit known seen facts.
Now tell em about dark matter and dark energy and gravity leak (joke, it's ok Coco, you have put more than enough effort into the above posts 
)
edit @PD ... I think they reckon there are many parallel (SP ?) universes all occupying the same erm space, all created by big bangs ... what's more, some think they can create new universes with an appropriate experiment ... Quantum physics is REALLY wierd from what I've seen
What direction is that star from us in relation to big bang ground zero ? At 600 million years after the bang .... if that star was on the opposite side of the bang to us then at most we could have been an equivalent 1.2 billion years away from each other when the light left it (I guess, if we were travelling in opposite directions
) ... so why has it taken 13.1 billion years to reach us . Surely we can't be accelerating away so fast ... but I'd have to get a calculator and convert to miles with light speed and those megaparsecs etc to work it all out Another thing I'm not sure of is ... why doesn't the Universe have a hollow centre (or does it) ? I'm guessing objects are moving away from the big bang ground zero at different rates, but even so
I suppose some objects trajectories have been changed due to gravity/orbital pull, maybe some have done a 180 .BTW This is just my poor battered imagination trying to grasp/make sense of things and filling in the gaps from tv documentaries etc
I'm not casting doubt on the big bang theory or any variation; the scientists would do that themselves if/as soon as it didn't fit known seen facts. Now tell em about dark matter and dark energy and gravity leak
(joke, it's ok Coco, you have put more than enough effort into the above posts )edit @PD ... I think they reckon there are many parallel (SP ?) universes all occupying the same erm space, all created by big bangs ... what's more, some think they can create new universes with an appropriate experiment ... Quantum physics is REALLY wierd from what I've seen
sry about the link tho, was in a hurry dident get to read it it all, but still had a valid point tho. There are sevreal things to back this up. I got it on a movie/documentary i have, but had trouble finding it online.
Think this is a bit better link http://bigbangneverhappened.org/
But ill try look up all i wanted to point out and give link later when i find em.
ill try to find the rapport i saw in NY time i think it was, their it pretty much was a bunhc of scientist denying facts & evidence.
Ill post links later, me in hurry again.
Think this is a bit better link http://bigbangneverhappened.org/
But ill try look up all i wanted to point out and give link later when i find em.
ill try to find the rapport i saw in NY time i think it was, their it pretty much was a bunhc of scientist denying facts & evidence.
Ill post links later, me in hurry again
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Your weirdness has been posted.
Your weirdness has been posted.