It is well organized, and it contains many facts useful for student-conducted research. It also features a section with weekly astronomy questions that allows students to e-mail their responses. Back to Top Click on any of the vocabulary words below to hear them pronounced and used in a sentence. A straight line about which a body or a geometric figure rotates. The union of atomic nuclei to form heavier nuclei, resulting in the release of enormous quantities of energy.
Fusion occurs when four hydrogen atoms are squeezed together to form two helium atoms.
Any of numerous clouds of gas or dust in interstellar space. A nebula is a giant cloud of gas and dust swirling around in space that will pull together, go through a chemical reaction called fusion, and produce the core of a new star. A celestial body orbiting another of larger size. Planet Earth has one satellite, the moon, revolving around it. The sun and the group of celestial bodies held by its attraction and revolving around it.