Codon Codon is a combination of three successive nucleotides in a DNA or RNA strand. All the nucleic acids, DNA and RNA, have nucleotides sequenced as a set of codons. Each nucleotide consists of a nitrogenous base, one of A, C, T/U, or G.
The terms solar eclipse and a lunar eclipse refer to events involving three celestial bodies: the Sun (âsolarâ), the Moon (âlunarâ), and the Earth. A solar eclipse occurs when the Moon lines up precisely in front of the Earth so that the Moon blocks the Sunâs rays and the Moonâs shadow falls upon the Earth.
Â©2014 by Fred Espenak. Introduction. An eclipse of the Moon (or lunar eclipse) can only occur at Full Moon, and only if the Moon passes through some portion of the Earth's shadow. The shadow is actually composed of two cone-shaped components, one nested inside the other.