Science Library - free educational site

Fusion

What makes the Sun tick?

Fusion is the combining of two nuclei to form a new species, accompanied by the release of energy.

Fusion energy is a much-vaunted possible alternative means of generating electrical power, but the technology still illudes us. However, the fact remains that most of the universe is driven by fusion power: in stars.

Our Sun is mainly hydrogen:

ElementPercentage composition
Hydrogen73.46%
Helium24.85%
Oxygen0.77%
Carbon0.29%
Iron0.16%
Neon0.12%
Nitrogen0.09%
Silicon0.07%
Magnesium0.05%
Sulphur0.04%

The Sun has been burning hydrogen fuel for about 6 billion years, and is about half way through this phase of its life cycle. When it has depleted a critical amount of its hydrogen, its radiation pressure/gravity equilibrium will be lost. It will initially expand to one AU (distance Earth-Sun) radius, losing a third of its mass, before collapsing. At this stage, the star will continue with helium fusing, resulting in the fusing of carbon and oxygen. The exact evolutionary path of a star depends on its mass.

Sun profile

Hydrogen on Earth is mainly the $^1_1H$ isotope, meaning it has only one proton in its nucleus, with a single electron. There are rarer isotopes of $^2_1H$, deuterium, and $^3_1H$, tritium. The nucleus of a helium-4 atom is known as an alpha-particle.

Under the conditions of extreme pressure and temperature of the Sun, the following fusion reaction occurs:

$$4^1_1H {→} ^4_2He + 2^0_1e + 2^0_1ν_e + ^0_0γ$$

The combination of two nuclei with low binding energy will release energy and produce a nucleus with higher binding energy.

Content © Renewable.Media. All rights reserved. Created : March 1, 2014 Last updated :May 18, 2016

Latest Item on Science Library:

The most recent article is:

Trigonometry

View this item in the topic:

Vectors and Trigonometry

and many more articles in the subject:

Subject of the Week

Computing

Information Technology, Computer Science, website design, database management, robotics, new technology, internet and much more. JavaScript, PHP, HTML, CSS, Python, ... Have fun while learning to make your own websites with ScienceLibrary.info.

Computer Science

Great Scientists

André-Marie Ampère

1775 - 1836

André-Marie Ampère, 1775 - 1836, was a French physicist and mathematician, who was a founder of the science of electrodynamics.

André Marie Ampére, 1775 - 1836, French physicist
IT Forum by Sean Bone

Quote of the day...

Ancient or not, the Seulpierre family as you will find it today is not really that different to any other family, here or there. Which means it is in every way unique.

Renewable.Media Internet Promotions

SaraOrdine