How do we know the age of certain things in space?

[baydude]

How do we know how old the earth is? Is it estimated? Why is it 4.5 billion years old and not 4.2? How do we know how old are other planets? How do we know how old the universe is and that it's forever expanding when we dont have proof?

 

[NuclearNed]

For the same reason we know the treadmill takes off and .999999.... != airplane.

 

[KeithTalent]

Probably aliens?

KT

 

[destrekor]

Science. It works.


or, if you prefer:

Magic.

or...

Magnets.

 

[FoBoT]

The age of the Solar System can be defined as the time of formation of the first solid grains in the nebular disc surrounding the proto-Sun. This age is estimated by dating calcium–aluminium-rich inclusions in meteorites. These inclusions are considered as the earliest formed solids in the solar nebula. Their formation marks the beginning for several long- and short-lived radiogenic clocks that are used to precisely define the timescales of Solar System events, such as the formation and evolution of planetary bodies. Here we present the 207Pb–206Pb isotope systematics in a calcium–aluminium-rich inclusion from the Northwest Africa 2364 CV3-group chondritic meteorite, which indicate that the inclusion formed 4,568.2  million years ago. This age is between 0.3 and 1.9 million years older than previous estimates and is the oldest age obtained for any Solar System object so far.

A. Bouvier & M. Wadhwa, Nature Geoscience (2010)

http://www.earthhistory.org.uk/questions-of-age/age-of-solar-system

 

[crownjules]

Magic. The answer is always magic.

 

[Ichinisan]

I've always wondered how we can test the age of rocks. The materials that compose the rock have existed (relatively) just as long as 99.9999% of the material on/in this planet.

 

[alent1234]

because scientists can do math more complicated than a + 3 = 7

 

[destrekor]

The age of the Solar System can be defined as the time of formation of the first solid grains in the nebular disc surrounding the proto-Sun. This age is estimated by dating calcium–aluminium-rich inclusions in meteorites. These inclusions are considered as the earliest formed solids in the solar nebula. Their formation marks the beginning for several long- and short-lived radiogenic clocks that are used to precisely define the timescales of Solar System events, such as the formation and evolution of planetary bodies. Here we present the 207Pb–206Pb isotope systematics in a calcium–aluminium-rich inclusion from the Northwest Africa 2364 CV3-group chondritic meteorite, which indicate that the inclusion formed 4,568.2  million years ago. This age is between 0.3 and 1.9 million years older than previous estimates and is the oldest age obtained for any Solar System object so far.

A. Bouvier & M. Wadhwa, Nature Geoscience (2010)

nuh uh! My pastor tells me science isn't always right.
And libruls will burn the world down like the heathens they are, or something like that.

 

[FoBoT]

I've always wondered how we can test the age of rocks. The materials that compose the rock have existed (relatively) just as long as 99.9999% of the material on/in this planet.

radioactive materials decay (change) where as inert materials do not decay (change) , so you compare the ratio in a sample

 

[Rubycon]

radioactive materials decay (change) where as inert materials do not decay (change) , so you compare the ratio in a sample

I grew up a radiodaughter. I always envied my LP friends. :biggrin:

 

[DrPizza]

How do we know how old the earth is? Is it estimated? Why is it 4.5 billion years old and not 4.2? How do we know how old are other planets? How do we know how old the universe is and that it's forever expanding when we dont have proof?

There is an abundance of proof. Why do you claim that there isn't evidence? Is it out of ignorance? Is it because you don't understand the evidence? Is it because you refuse to accept the evidence because it conflicts with your own views?

edit: and that it's "forever" expanding was a HUGE question until just a few years ago. There were questions about the geometry of the universe, and that would ultimately determine the universe's fate.

 

[Merad]

For the same reason we know the treadmill takes off and .999999.... != airplane.

 

[Atomic Playboy]

We cut it open and count the rings.

 

[BoomerD]

We cut it open and count the rings.

Or just look at either the "born on date," or the "best used by" date that's always on space objects...duh.

 

[amdhunter]

because scientists can do math more complicated than a + 3 = 7

a = 10

 

[SandEagle]

i confused you for busydude

 

[Phoenix86]

Science. It works.


or, if you prefer:

Magic.

or...

Magnets.

 

[polarmystery]

Most of the time I hear people claim there isn't proof of evolution, universal expansion, gravity, quantum mechanics etc. it typically stems from their refusal to take the necessary steps to understand science or methods that are both verifiable and provable. They don't like that there is not a quick answer to everything and don't want to bother doing the research for themselves. That, or they simply do not have the mental capacity to comprehend all of the data.

 

[KeithP]

My pastor tells me science isn't always right.

Science is always correct until scientist say it is not and propose something new. If someone that isn't a scientist say science is incorrect, they are wrong.

Duh.

-KeithP

 

[JulesMaximus]

How do we know how old the earth is? Is it estimated? Why is it 4.5 billion years old and not 4.2? How do we know how old are other planets? How do we know how old the universe is and that it's forever expanding when we dont have proof?

We know the speed of light and we do have proof that it is expanding.

 

[GrumpyMan]

Hello......just scan the mobile barcode on space objects and it takes to their web site where the age is given. There's an app for that.

 

[Ichinisan]

I've always wondered how we can test the age of rocks. The materials that compose the rock have existed (relatively) just as long as 99.9999% of the material on/in this planet.

radioactive materials decay (change) where as inert materials do not decay (change) , so you compare the ratio in a sample

So wouldn't all rocks on our planet be about the same (relative) age? Are we measuring the age of the material from before it became part of our planet?

 

[CZroe]

radioactive materials decay (change) where as inert materials do not decay (change) , so you compare the ratio in a sample

You didn't understand the question. Also, you don't always compare a ratio of decayed radioactive materials to inert materials, you compare a ratio of a radioactive material with one decay or accumulation rate to a radioactive material with another. He wants to know why one terrestrial rock is newer than another when the material in both of them has been here since the planet was molten.

 

[Braznor]

One terrestrial rock can be different from another because while the atoms and molecules of both the rocks have been present on Earth since the creation of the planet. the internal structure of the individual rocks would make them different in the eyes of a geologist.

A certain rock could be the surface of the planet, one from the mantle, one rock could have formed four billion years ago and another just a million. They are all composed of the same atoms and molecules since the birth of the universe, but the way they are bonded and their composition could give vital clues or glimpse of Earth's seismic history.