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Is Earth's core as hot as the surface of the sun?
Question Date: 2014-09-14
Answer 1:

The temperature of the Earth's core is not known as well as the temperature of the Sun's surface (photosphere)! Is that not amazing? The distance from Goleta to the center of the Earth is 6300 kilometers; the distance to the Sun is 93 million miles!! Yet we know that the Sun's surface is 5800 degrees Kelvin. For the Earth's core we can only estimate that its temperature is about 6000- 7000 Kelvin; actually it could be a little higher or lower, we do not know its value so well.

So, as a decent guess we can say that the temperature of Earth's core is ABOUT the same as the temperature of the Sun's photosphere, of 5800 degrees Kelvin .

Answer 2:

Discoveries in the last 2 years do actually show that the Earth's core is a similar temperature to the surface of the sun (which is about 5778 Kelvin=5505 Celsius). Scientists don't have a good way right now to directly measure the Earth's core temperature, but they can do experiments above ground to get good estimates.

The French scientists who made the most recent estimations knew that the Earth's core is made of iron, so they made very careful measurements of the melting point of small bits of iron in very high pressure chambers above ground to simulate what it's like at the core. They found that the Earth's core is about 6000 C.

The temperature of the sun's surface is actually much easier to measure. The sun's temperature is measured by "spectroscopy" which refers to the analysis of light and color. The color of the light emitted from hot objects (also called "black bodies" in science) corresponds to certain temperatures. Astronomers can use spectroscopy to know the temperature of just about any clearly visible star.

Answer 3:

Yes. Scientists recently measured the melting temperature of iron at very high pressures to determine that the temperature at the boundary between Earth's solid inner core and liquid outer core is 6000 degrees Celsius. (If you are interested in learning more about how they did this, here is a link to an article about it:

click here to read).

Meanwhile, the surface of the Sun is only about 5500 degrees Celsius. Keep in mind however, that the surface of the Sun is the coolest layer of the Sun; the corona, the outermost layer of the Sun's atmosphere, is about 2 million degrees Celsius and the core of the Sun is about 15 million degrees Celsius.

Answer 4:

The core of the Earth is around 6000 degrees Celsius, or 10,800 degrees Farenheit. The surface of the Sun is about 5500 degrees Celsius, or 9900 degrees Farenheit. So, the core of the Earth is hotter than the surface of the sun. However, the core of the sun is 15,000,000 degrees Celsius or 27,000,000 degrees Farenheit. Wow!

Answer 5:

Great question! First, the Earth's core is made of a mixture of iron and nickel. It also has two parts: an outer liquid core and an inner solid core.

The edge of the outer core is about 4000 degrees Kelvin (7000 degrees Fahrenheit). The inner core is about 6000 degrees Kelvin (10 000 degrees Fahrenheit) and that IS as hot as the surface of the Sun!

The inside of the sun is much hotter of course (~20 000 000 degrees Fahrenheit!), because of the nuclear reactions that release heat from the center of the sun.

If you want to know why the Earth's core is so hot ask us next week!

Answer 6:

The Earth's core is about 8,000 degrees Celsius or Kelvin grades (C and K aren't that different at that temperature). The surface of the sun is between 5,000 and 6,000. Thus, the Earth's core is hotter. Of course, the sun's core is hotter yet, at about 14,000,000 Kelvin.

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