# Will we ever get to the center of the earth?

#### mrfeathers

ok so heres my theory. i know that the center of the earth is the most dense spot on the planet, ant that is why it is "molten lava" because the particles are moving so fast. So even if we had machines that could withstand the heat, wouldnt we not have a machine powerful enough that is capable of drilling through the rock because it is so incredibly dense?

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#### Gamecubesupreme

*watches The Core*

#### tony873004

Gold Member
I doubt the density of the rock would have much to do with it. Rock of itentical make-up at the core should be similar in density to rock on the surface. For example, 33 feet below the surface of the ocean, pressures are 2x surface pressures. But if you skin dive down to the bottom, pick up a rock, bring it to the surface and measure it, it's density would be virtually indistinguishible from a surface rock. Rock is not compressable like air.

Also, as you get deeper, gravity gets less. This may cause less pressure.

#### Janus

Staff Emeritus
Gold Member
tony873004 said:
I doubt the density of the rock would have much to do with it. Rock of itentical make-up at the core should be similar in density to rock on the surface. For example, 33 feet below the surface of the ocean, pressures are 2x surface pressures. But if you skin dive down to the bottom, pick up a rock, bring it to the surface and measure it, it's density would be virtually indistinguishible from a surface rock. Rock is not compressable like air.

Also, as you get deeper, gravity gets less. This may cause less pressure.

While rock is not as compressable as air, it is compressable. Estimates place the density of the center of the Earth at 13 g/cm^2, over six times that of the crust.

The biggest problem would be pressure, at 3.5 million atmos. It doesn't matter that the local gravity decreases with depth, you still have all the weight of the rock above you pressing down on you.

#### Astronuc

Staff Emeritus
tony873004 said:
Also, as you get deeper, gravity gets less. This may cause less pressure.
The pressure increases as one travels toward the center of a planet, because gravity is pulling down the mass of material from above.

Pressure is approximately 350 GPa at the center of the earth = 3 454 231. atm or 50 742 660 psi.

1 atm = 760 mm Hg = 760 torr = 14.69 psi = 1.013251 x 105 Pa at about 25°C.

Furthermore, estimates on the temperature at the center of the earth are in the range of 5300 - 7300 K. Graphite sublimates at about 3705°C (3978 K), but in the center of the earth, the graphite might dissolve into the surrounding metal. HfC has a melting temperature of 3888°C (4161 K), which is still below the above range.

See - Temperature at the Center of the Earth

#### Janus

Staff Emeritus
Gold Member
mrfeathers said:
ok so heres my theory. i know that the center of the earth is the most dense spot on the planet, ant that is why it is "molten lava" because the particles are moving so fast. So even if we had machines that could withstand the heat, wouldnt we not have a machine powerful enough that is capable of drilling through the rock because it is so incredibly dense?
Even though the core is hot enough for it to be molten, it is under such high pressure that it is actually solid.

#### Mr. dude

I don't think we will ever reach the center of the earth. Even if we made a machine that could withstand the pressure, I think it would probably melt. And if it didn't, the people inside would unless there was some kind of cooling system. Even then the probability of reaching it wouldn't be very high.

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