What heavier element is created when hydrogen atoms fuse together in the sun’s core?

Helium is created from hydrogen in the sun's core.

Four hydrogen-1 nuclei fuse to produce

Explanation:

Step One:

.

Two hydrogen-1 nuclei fuse. One proton will convert to a neutron. The products will be

Step Two:

.

There are plenty of hydrogen-1 nuclei available in the core of the sun. The hydrogen-2 nucleus from step one will fuse with a hydrogen-1 nucleus. The product is

Step Three

.

Two helium-3 nuclei from step two react with each other. The products are:

The overall reaction will be:

.

In other words, hydrogen nuclei in the core of the sun fuse together to form helium.