How old is the earth, and how do we know?

Squee! Learned something new here. Fission track dating. Neato! =^_^=

"We don't know exactly because direct dating of the earliest material on the surface of the Earth will only tell use a minimum age;.." This was a 'duh' for me, I'd never though of that! Thank you for the interesting article, now, curiosity piqued, I will have to look for more reading. Thanks for the cites to get me started! :)

Fission track Dating: That's a thing that shows that the moon rocks were not faked. When the moon rocks were brought back and examined, these tracks were discovered. It took a bit of sleuthing to figure them out. They were not expected. Faked moon rocks would not have contained them.

"Some meteorites are known to be fragments of Mars." How do we know this?

In short, because they are made of Mars stuff. We know something about what mars is like chemically and isotopically, and a set of meteorites (fewer than 100, IIRC) have these characteristics.

Also keep in mind that there are several hypotheses that suggest that the moon is the result of a collision with the Earth and another body.

If that is the case, then even moon rock material is much younger than the age of the Earth.

It would have been a molten earth, though. Then, the moon would cool much more quickly and the surface rocks subsequently remaining intact, relative to those of the earth. The whole transformation from molten blob to encrusted blob would have been tens of millions of years. Somewhere in there is the "gray area" of dating the first thing we could call "Earth".

Thanks, Greg! I have another question for you. Why is the ocean salty?

Mike@#7: Surely you're not serious! If you are:

Why is the ocean salty?

Because rivers carry soluble minerals, some of which taste "salty", into the oceans. The concentrations of the various solutes reflect the equilibrium of solute entry into the oceans and their loss from the oceans.

Maybe you should have asked: "Fuckin' magnets. How do they work?"!

martindh: Ah, yes, but you are missing the anthropological slant on the ocean's saltiness!

As for magnets: You can't explain, that!

In short, because they are made of Mars stuff. We know something about what mars is like chemically and isotopically, and a set of meteorites (fewer than 100, IIRC) have these characteristics.

Re #9; I liked Feynmann's discourse on magnetism and refusal to give a simple answer to the question of "what's that force I feel between two magnets" or something similar.

http://www.youtube.com/watch?v=wMFPe-DwULM

Cool information. What is it about these dating methods that detractors try to say isn't accurate? It seems to me there can't be much room for subjective observations and data in these methods. So what gives?

Sondrah, good question. People pick and chose what they here. For instance, bold and daring scientists tried to take C-14 dating to before 30,000 years ago using new techniques and had all sorts of trouble. The creationists then claimed that all dating techniques don't work. Meanwhile, the scientist mostly gave up on pre-60,000 dates with C-14 but managed to extend into that range between 30,000 and 50,000 K with good samples. It is also the case that a "radiocarbon" year is not the same as a calendar year and there is a calibration one must do, and we fight over the calibration methods. But the method still works. It's like car-jocks fighting over engine capacity vs. horsepower vs. torque as the best way to compare engines (sort of).

In another instance, it was discovered that there is a category of volcanic ash that you could not date with Potassium-Argon dating. There were lots of samples dated by in retrospect the samples were all wrong and it did not seem easy or possible to figure out when the system was working vs. not .

That confusion lasted for about two or three years, when a) it was determined that certain ashes could not be dated and other's could, but those that could not be dated could be easily identified (and still used as markers); the, b) they figured out how to date the 'difficult' ashes anyway; and c) the new technique came with a nifty advantage: The lab results would tell you both the date and whether or not the date was any good.

In each of these cases, creationists picked a scientific argument, reported only parts of it, used the fact that there was an argument to totally discredit the entire field, and when confronted with the truth, punted. And by "punted" I mean "lied."

(And that's why people are so mad at the Creation museum ... THAT's the guy who did most of this ... same person, same organization, same web sites, same funding sources, etc. etc.)

About 6000 years old give or take about 500 years.

How do we know? From now back until Jesus' time it has been roughly 2011 years. From Jeus back to Abraham is roughy about another 2000 years according to geneology records. From Abraham back to Adam was somewhere in the neighborhood of about 2000 years ive or take a couple hundred years. Based on geneological records 6500 years is an accurate measurement.

Now, as far as 'science" goes, can ignore certain things like the grand canyon, continental drift, etc simply becuase these things happened relatively quickly (a few hundred years or less)as a result of the great flood that Noah was a part of.

After the flood many animals did die out as a result man hunting them to extiction for food. Some animals such as dinosaurs (dragons) may have been hunted for sport or defense. The mountains we see today were not as high as they were in the time of Noah. Theses mountains were pushed higher and continents broke apart as a result of the devastating 40 day flood that covered the entire globe. Modern dating methods are ok if trying to find the age of a dead body found in the woods, but there are too many factors that influence the results to be accurate and come up with "millions of years" type stuff.

All those fossils we find are buried deep as if they were buried in a FLOOD! The deeply buried fossils, numerous petrified forests, deeply buried trees, etc. all are evidence of a global flood.

So, 6500 years is how old the earth is. Of course some will argue over that, but we conservatives will continue to teach it regardless of what FLEEBAGGERS think about it.

Even looking at this guy's site I can't figure out if he's a Poe or not. The comment @ 14 (besides being wrong from top to bottom) has a hint of over-the-top lunacy that certainly suggests it, and his website veers from quoting Natural News about fluoride to Conservapedia about socialism to Big Brother tracking people by putting transmitters in pills.

70+ posts over the last 12 months with nary a comment. If he isn't a Poe, he's doing his best cross between Mabus and John A. Davidson.

I thought TSKIA might be a poe, but a glance at his website shows he's really a moron.
Point: He boldly gives this "quote" and attributes it to Jefferson:

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

Our local teabaggers got caught with this one as well. A quick search at the Jefferson encyclopedia shows this:

This exact quotation has not been found in any of the writings of Thomas Jefferson. It bears a very vague resemblance to Jefferson's comment in a prospectus for his translation of Destutt de Tracy's Treatise on Political Economy: "To take from one, because it is thought that his own industry and that of his fathers has acquired too much, in order to spare to others, who, or whose fathers have not exercised equal industry and skill, is to violate arbitrarily the first principle of association, âthe guarantee to every one of a free exercise of his industry, & the fruits acquired by it.' "

I assume the poster uses it for the same reason the local teabag folks did: when asked "This version is easier to remember".

When you realize that long sentences are too confusing for these folks to handle, it's no wonder they prefer mythological explanations for our world over the scientific.

I'd add to the explanation on why sea water is salty; of course, you may have tasted river water and noticed it didn't seem salty at all, so you wonder how the dissolved mineral salts can be so noticeable in the ocean.

Pure water turns to vapor more easily than salty. When the water does warm up enough to rise into the atmosphere, the salts are left behind and the rainwater is freshwater. Billions of years of water washing salt into the ocean and rising again into rainclouds has concentrated the salt levels in it.

Billions of years of water washing salt into the ocean and rising again into rainclouds has concentrated the salt levels in it.

Is the ocean's salinity slowly increasing, then? Or has it stabilized?

Related: what processes remove salts from the ocean? Is the primary sink for these materials in subduction zones, pulling material down below the crust?

The salinity of the ocean is constantly changing across space and time in a complex way that actually drives ocean currents and affects one of the primary roles of the ocean: Absorbing, storing, moving, and releasing heat.

As far as change over time goes, that's interesting. It is possible (though this is speculation) that the salinity of early seas was very variable as during the earliest formation of the ocean water was being added to the system on a regular basis, as were minerals.

"Salt" (ions of various kinds, with Chloride, Sodium Sulfate and Magnesium topping the list) is added to the ocean all the time as fresh (= impure) water washes into the sea and evaporate (nearly pure vapor) leaves it. However, salts leave the ocean as well. Sea spray, incorporation into bottom sediments, basins isolating and then drying up, etc. remove dissolved salts. Big parts of the Mediterranean are underlain by several feet of salt crust that formed there when that sea had an evaporation rate higher than the input from the Straits of Gibralter for several thousand years during the "Messinian Salinity Crisis" for instance. All those "shallow seas" fossilized in widespread limestone and preserved reef deposits contain (among other things) salts that were once in the ocean and are now seen in road cuts and rock shops. Sea floor sediment containing salts condensed out of the ocean are eaten by the planet when they are subucted, to return later, perhpas, as the effluence from volcanoes.

And, the amount of fresh water in the ocean is not constant. The major contributing factor to that is probably glacial size, over the medium to long term .

On balance we might expect any "ocean" (lowest-point basin) to get saltier over time but the salter the water is the stronger are some of these removing effects. The Dead Sea (saltiest body of water on the planet) is surrounded by a zillion tons of salt crust, but such died "sea salt" is less abundant adjoining regular ocean, for example.

So yeah, it's a fairly complex question!

@18 This is a tricky question. I would imagine with the forming of polar icecaps the world's oceans became more saline. Thinking about it in geologic time though, my guess is mineralization of sediment(aka: diagenesis)vs erosion rates would probably be the biggest factor. Subduction would make things tricky because it is a good way to get some of the heavier ions back into the mantle but seems to "prefer" putting the lighter ones back via vulcanism. These lighter ions are the cause of the salinity in the first place. Because of this overall feedback mechanism I would guess that over time the oceans will become more saline just like the crust is slowly becoming more SiO2 rich.

the ocean is salty because all the angels are crying into it cuz we think the earth is billions of years old.

lol.

"Big parts of the Mediterranean are underlain by several feet of salt crust that formed there when that sea had an evaporation rate higher than the input from the Straits of Gibralter for several thousand years during the "Messinian Salinity Crisis" for instance."

The Mediterranean Sea could not possibly evaporate faster than the Atlantic Ocean could flow into it, as long as they are connected by the Straits of Gibraltar. I think what you mean is that the Mediterranean is evaporating faster than fresh water is flowing into it from rivers and rain. This happens in the present, but the deficit is made up by flow through the Straits. What caused this event in the past was that the Straits were completely closed, allowing the Mediterranean to (largely)dry up.

That is correct. I was thinking of the old model in which the mechanism or evidence of the straits closing completely was missing and unbelievable evaporation had to be believed. Thanks for pointing that out.

it isn't a matter of opinion. the earth is the age that it is. if someone says it is 1,000 years old and another says it is 1 billion, they aren't both right in their own way.
based on the EVIDENCE we can measure the age of the Earth to be 4.54 billion years old (± 1%), a lot of people will say that the Earth is <10,000 years old because the bible says so, but they are simply wrong there is no other way you can put it.
http://ezinearticles.com/?Best-Wrinkle-Cream-Review---Tips-to-Select-Be…

The Mediterranean Sea could not possibly evaporate faster than the Atlantic Ocean could flow into it, as long as they are connected by the Straits of Gibraltar.

There was a waterfall where the straights of Gibraltar are now the flow in was less than the evaporation out, the whole bottom of the Mediterranean was below sea level. At some time the damn which separated the two really broke and the med became a sea. Glad I was not living below at the time!

Oh ya. The Messinian Salinity Crisis is one of those things I pull out to show people why I think geology is really, REALLY cool.

Re: Salinity.
The question may have been raised by #7 in connection with the age of the earth because some Creationists believe that you can calculate the age of the earth by assuming a steady increase in salinity since the oceans were created. (Giving a young age conveniently.) The folly of that idea is debunked here: http://orgs.usd.edu/esci/age/content/failed_scientific_clocks/ocean_sal…

According to Hinduism the age of earth and cosmos perfectly fits into their ancient calculations of vedas. Here's the link and source.....http://en.wikipedia.org/wiki/Hindu_creationism

Hindu cosmological view of creation

The Hindu cosmology and timelines in a way is the closest to modern scientific timelines and even more which might indicate that the big bang is not the beginning of everything but just the start of the present cycle preceded by an infinite number of universes and to be followed by another infinite number of universes. The Rig Veda questions the origin of the cosmos in:
Neither being (sat) nor non-being was as yet. What was concealed? And where? And in whose protection?â¦Who really knows? Who can declare it? Whence was it born, and whence came this creation? The devas were born later than this world's creation, so who knows from where it came into existence? None can know from where creation has arisen, and whether he has or has not produced it. He who surveys it in the highest heavens, he alone knows-or perhaps does not know. (Rig Veda 10. 129)
The later puranic view asserts that the universe is created, destroyed, and re-created in an eternally repetitive series of cycles. In Hindu cosmology, a universe endures for about 4,320,000,000 years (one day of Brahma, the creator or kalpa) and is then destroyed by fire or water elements. At this point, Brahma rests for one night, just as long as the day. This process, named pralaya (Cataclysm), repeats for 100 Brahma years (311 trillion, 40 billion human years) that represents Brahma's lifespan. It must be noted that Brahma is the creator and regarded as God in Hinduism.

Hope it helps some of the readers with modern findings by scientist

Hmmm, we know that the sun's diameter is shrinking by 0.01% per century, to put it easier for the layman to understand, the sun is getting smaller by about five (5) feet per hour. This has been a constant since at least 1755 and for all we know, it has always been so.

Problem:

If this is true, which observations prove. That would put the sun's outer edges within the earth's current orbit, just over 20 million years ago. Therefore, I'm not buying into this 3 or 4 billion year estimate. Please feel free to offer an explanation. Did the sun shrink more slowly in the past? Or is the earth's orbit getting smaller? Or is the earth significantly younger than you estimate?

Marc--

Three step process, here--

1. Google "Is the sun shrinking?"

2. Watch and listen to the YouTube videos explaining why this is nonsense.

3. Stop letting the creationist scam artists play you for an idiot.

The total mass of the sun will decrease to abotu 99.966% of its current mass by the time it goes through its expected transition (engulfing the earth then becoming a new kind of star).That will be over several billion years. So no, it can't be losing five feet a year.

Observations of the sun extrapolated back beyond your fictional mid 18th century date to the earliest astronomers of several thousand years back would indicate that the sun would have been much much larger then. But it wasn't.

If, on the the other hand, the earth really is several thousand years old, then the decay rates of radioactive isotopes are not what is currently calculated, and all of the nuclear technology being used in the world today ... from nuclear medicine to nuclear power plants to nuclear weapons ... can't be happening.

Yet it is.

It saddens me that the fundamentalists don't understand science is a 5 step method and if that method is not used then what they claim isn't science. In the same way that English lit teaches English, History teaches the past, science is Observation, formulating a hypothesis (the word most Christians mean when they improperly say 'theory'), testing, and formulating a peer reviewed theory while being open to change. Religion says, we know the answer and we can make anything look they way we want as long as you don't ask too many questions and those answers and stories were all created by Neolithic Iron age desert dwellers! Religion is threatened by knowledge and if there is a God they actually believe they have nothing new to learn about a deity of that magnitudes process. They call atheists arrogant for wanting to learn truth but how arrogant do you have to be to believe your version is all there is? Science never says, "this is it" because it is the process of understanding and learning and there is always something to learn.
What would happen if there never was a god? Things would be as they are. When they site their proof it's usually misquoting, misrepresenting, real scientists and using lawyers or theologians to argue.
The Bible is a source of evil, if you don't believe me look at Leviticus, a book that approves of slavery, it approves killing your children for disrespect, it approves of pulling out your child's eyes, and commands all Christians wear beards (this is also the same page that says homosexuals are evil, amazing how they pick and choose).
Why can't Christians just decide to be educated?
The Earth is not 6,000 years old and there are absolutely no scientists who believe there are.
Why Christians lump the astronomical world into evolution (as though both disciplines do not require 8 years or more just for a doctorate and a life time to understand) yet they can sum both up in a web page!
Arrogance, ignorance, and it's shameful. When will the educated finally say enough is enough? We need to stop these people from having a say in education. We need to silence them.
If you believe in God there is no reason to not accept that God created the Universe and humanity as science describes.
The Bible says the Moon gives off light.
The Bible says light was created before the sun.
The Bible says that the stars were created after the sun though the sun...is a star!
These people believe in demons, angels, and whales swallowing fisherman.
These people believe in virgin births (though in that region there are countless myths of virgin births including the Greeks, Persians, Babylonians, Egyptians, and more).
These people don't understand that Adonis (Lord as in anno dominae) was murdered by a disciple, placed in a cave, and a week later rose from the dead 800 years before the Bible.
They don't know the origin of their own religion, how all Bibles were destroyed except those rewritten by very drunk Irish monks.
These people don't know that books were removed from the Bible that the Catholic church deemed a threat and yet they read it as if it were true?
We intelligent, educated, people need to ignore their claims that the science mind is arrogant and narcissistic( a destructive mental condition which results in a warping of reality and not a personal attitude but if you stopped listening to pastors and read you'd know that)but science shows us how small we truly are.
Christians, no matter what, believe they are going to heaven because they are wonderful people though each christian group disagrees with one another.
Lastly, when you want to teach "creation" you must also understand this is the United States where all citizens pay taxes and if you must represent your views in science then you'd also expose your children to the origin story of every other religion that also pays taxes.
Never thought about that.
Science class is not controversy class. If you can't prove god then you can't teach it and as far as I know there is no proof for god.
The eye btw is a very easy, not complicated mechanism prone to extreme number of failings and if you went to school and actually paid attention you'd know that.
Finally, Christians argue that the contradictions in the Bible with the rules of slavery and murder as well as anti homosexuality and racism are all parts of the older Bible and the new Testament is where it's at.
If that is true then why read Genesis? Who dictates which portions are true and which should be ignored?
Do you support slavery? The Bible commands you must.
The Bible also commands you don't use Christmas trees because they are pagan yet i'm sure you celebrate Christmas.
Hypocrites and intellectual morons should not be allowed to speak.
Why is it Scientologists who believe (and support with their own evidence) that the Universe is trillions of years old, and Xenu the intergalactic overlord created the soul on Earth. Sounds stupid doesn't it? Yet I can't prove they are wrong so we should teach that too?
The only reason Christans aren't laughed at is because we have heard their stories for nearly 2000 years enough times that it culturally isn't strange to hear anymore but I guarantee it's no weirder then Mormons claiming when you die you get your own planet and that Yahweh was a ruler of a planet and lucifer and jesus were his sons who came to Earth to help convert north American natives.
What?
It's no weirder then a dude who walks on water and is the son of a god.
For interesting reading of how Jesus is a rip off myth of Mythras (also a son of god, committed miracles, died for sins, and was reborn) maybe you should learn more about jesus from outside your bubble before you decide to spread more stupidity.
Sorry, I have just reached my limits on how stupid this country is becoming, how it is fallen behind the rest of the world in education, health, and economics and it's all because of Christians.

Thank you for educating me and replying to the questions which broke it down even more!

Science may not have all the answers but at least there are people who are dedicated to trying to find and explain them!

Thanks. Gracias. Merci. Danke. Takk. Dankie.

The bible says the earth is about 6,000-7,000 years old, but scientist believe it is 4.7 billion years old which is impossible. This is correct because of 6 reasons. You can see these 6 or more reasons at How old is the earth? - Answers in Genesis. I also did some research using a magazine of mine called Christ of the nations: special edition February 2011. It says that the earth can't be 4.7 billion years old because Niagara falls recedes 2.5 feet a year. If the earth was 4.7 billion years old, Niagara falls would have reached the ocean. Also the moon is drifting away from the earth 2 inches a year. If the earth was 4.7 billion years old the moon would have started 148,358 miles closer to the earth. Therefor causing catastrophic global flooding twice a day. But, if the earth is 6,000 years old the moon only started .2 miles closer to the earth. This proves that the earth must be 6,000- 7,000 years old.

Look scientists u isn't have to say it Luke that shut up and accept God and if u Don ur going to go to hell

Jason,
I'd like to see legitamate documentation that all bibles were destroyed except one rewritten by drunk Irish monks. I agree that many many... OK one more...Many Christians are arrogant and ignorant about how their own religion originated. And way to many know nothing of apologetics. Damn shame. That said I think that if you truly are wishing for education, that ALL, theories/hypothesis/dreams/revelations , or whatever else you want to throw in there, of our human existence should be covered in school.
Also how the hell do you say that our economy is falling because of Christians? How the fuck are they even related? (Chirp chirp chirp) oh that's right they aren't. You may be tired of hearing that God made the world in seven days according to a collection of historical documents, written by over 40 different authors on different continents over a span of over 1500 years, and the authors were eye witnesses who wrote the "books" during the life span of other eyewitnesses.
But would you like to know what I am tired of? I'm sick and tired of hearing that the bible is full of shit by people who Google why the Bible is wrong swallow it hook line and sinker and then proceed to misquote the bible and rant about the uneducated. Educate yourself in the bible and theological history because you sound like some fuck-tard that doesn't know shit. The bible never condones racism, nor bans Christmas trees. For Pete's sake Christmas wasn't celebrated by anyone in its current form with trees and the lot until well after the bible was written. For you to make such an argument shows that you should not speak because, and I quote, "hypocrites and intellectual morons should not be allowed to speak".

Tyler Needham, the bible doesn't exactly "ban" christmas trees, but there is only one mention of a decorated tree, and it was placed at the grave of Nimrod, who was not beloved of god. Similarly, Jesus never said to celebrate his birthday, and in the bible the only birthday that is specifically celebrated is that of Herod.
This is why, for example, the Jehovah's Witnesses do not celebrate Christmas. It was created long after the time of Jesus by people who were already used to celebrating the Saturnalia at the end of the year. It is a pagan holiday, laden with pagan traditions, that Jesus never told us to celebrate.

To add to my previous comment regarding christmas trees, I refer the reader to Jeremiah 10:2-5:
"Thus saith the Lord, Learn not the way of the heathen, and be not dismayed at the signs of heaven; for the heathen are dismayed at them. For the customs of the people are vain: for one cutteth a tree out of the forest, the work of the hands of the workman, with the axe. They deck it with silver and with gold; they fasten it with nails and with hammers, that it move not. "

Fairly interesting. Not really here to have a go at any one person or group, but i would suggest that free speech includes points of view you do not agree with. I would also suggest that there is quite a difference between rational discussion of a particular point of view and attempting to impose that point of view on another. For example: I happen to be of the opinion that reading a book compiled many hundreds of years ago and beliving it to be anything accept a comentary on the times in which it was (variously) written is a mistake. Thats an opinion. I am quite happy to rationally discuss why i belive that. What i cant and wouldnt do, is try to convince anyone else that my view is "correct". People have to discover their own truth. If they choose to belive a thing, then that is fine. If they try to convince me with rational argument, that too is fine - i am willing to enter that debate. However, if they are closed to any arguement except their own, then there isnt really discussion to be had..it is not so much discussion as dogma. Dogma is a statement that accepts no alternatives or questions . I strongly belive (in certain things) , but im happy to entertain an alternative.
If discussing something makes you angry, dont.

Hi Everybody Yes certainly what you are reading now is not Science at all because scientists call it research. I.e. to search again ...Even a scientist like Albert Einstein was really puzzled how Indian new so much about the Cosmos .It does not make me a person who does not love god .I believe a lot in Jesus. We do not want to buy a specific reality because we think science does not match with it...neither does god match with science.Some of you say sun,moon, have you ever tried doing a reverse calculation before saying its wrong..Even one of the biggest scholars had to say "I know that I know nothing' We have just reached 2 planets till used to think the world was flat.So many of the scientific conclusions have gone wrong. Let us lead a happy life since when ever we look back and don't know we become rigid ..Scientists say earth is 4.5 million years old

i do know one thing you can tell you dum ass libs by the shit you say i bet one thing i bet i can kick the shit out all you fag libs

Steve, thanks for the thoughtful and insightful comment.