What is the Minimum Temperature Required to Fuse Hydrogen Atoms?

-- GAREBO | August 25, 2020

Question:

Hi Doctor Jeff,
Mary Mayo gave me this link, bless her heart;.and, thanks for taking my question.
I’ve read that fusion requires a minimum start-up temperature far greater than the temperature of the Sun’s core.
Quite confusing for me.
What is the minimum temperature required for fusion; and,
what is the Sun’s core temperature?
If “start-up” is greater, please explain.
Thanks again, Doc !

-- GAREBO

Answer:

In order to fuse two hydrogen atoms two things are required: high temperature and high pressure. The minimum temperature required to fuse hydrogen is about 100 million Kelvin, which is about six times the temperature in the core of our Sun. The pressure required must be high enough to force the hydrogen nuclei within 10^(-12) millimeters of each other. Note that the Sun attains the high temperatures and pressures needed to fuse hydrogen over a very large area by virtue of its very high mass, while on Earth we are able to fuse hydrogen over only a very small area using magnetic fields and lasers to compress and heat the hydrogen atoms.

-- Jeff Mangum

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