Exactly how old is the World?

Answer 1

The world is about 4.5 billion years old.

Answer 2

Like the rest here, I've also read that the Earth is about 4.5 billion years old. I think that figure came from carbon dating as well as other techniques (I can be wrong about that one).

What I have never read about is when did they start counting. Was that the time when the Earth first started spinning as a cloud of gas? How do you define started spinning? Was it from the first millineum when the clump of gas got detached from the Sun? Again, how do you define got detached?

If it is true that the estimated age of the Earth came from carbon dating, then the point of origin may well be when we first started having carbon. If our definition of the birth of the planet is based on something more fundamental, like when the gas started to break out of the Sun, then probably the age of the Earth can be considered to be older than the age of carbon.

I'm just thinking aloud, but I could be wrong about these.

Answer 3

Since I am the center of the Universe then the World is almost 40 years old. I would like to thank you all for showing up to make the world an interesting place to be.

Answer 4

This question has already been answered, but the question raised about "when did they start counting the Earth's age" is a good one. Since they used small crystals called zircons to make this age-determination, the simple answer is that we start counting how old the World is when the early Earth started to solidify from a molten mass.
Scientists like to use zircons because these crystals are very good at surviving any subsequent reheating, intense pressure, or erosion. And because these crystals contain lead isotopes that are the product of radioactive decay of uranium, scientists can measure this rate of decay and deduce the age of the zircon crystal, and hence, when the Earth started to solidify,
But, in order to measure the age of things older than the Earth, scientists have to turn to other rocks that are even older. Fortunately, we have some of these rocks, and here on Earth we call them, "meteorites". Yes, most meteorites are older than our own Earth. Some meteorites even contain fragments of matter that predates the birth of our Sun. In fact, meteorites form the baseline from which age-dates for everything in our Solar System is determined.

Answer 5

It seems to be quite old - certainly before my time. Unfortunately, no-one kept an accurate diary at the time, so we've only got the word of the supposed experts. 200 years ago, it was generally agreed that it was getting on for 6,000 years old. Now the best guess is about 4.5 billion years old - but when you ask is that British or American billions, the wise guys go quiet on you.

Answer 6

The current consensus is that the Earth is about 4.5 billion years old.

For a great overview of how they know this, read Bill Bryson's excellent book A Short History of Nearly Everything.

For the poster above, carbon dating has nothing to do with it - that can only be used to date things going back to about 60,000 years so would be useless for measuring the age of the Earth.

Answer 7

Around 4.5 billion years (unless you're a fundie, in which case it's about 6000 years). The Universe is believed to be about 14 billion years old. That means that the earth is a late-comer (though not too late). We humans (homo sapiens) have been around for about the last 130,000 years or what amounts to a very brief moment compared to the Earth.

Answer 8

As well as the zircon dating system there is also the dating that takes place from the meteorites. The oldest we find and can date in this solar system all come out at around the 4.6 billion year mark. (4,600 000 000). The early formation of the system is still abit shakey but the oldest thing you find in a box is a good estimate for the minimum age of the box. (only an analogy so don't be stupid)

Answer 9

Nobody know EXACTLY how old it is but it is estimated to be about 4,500 million years old or four and a half billion years as it's normally written, give or take the odd few million of course.

Answer 10

Roughly 4 billion years.