Psychology Glossary. Genotype. The total set of genes contained within an organisms cells. Organisms contain some genes that are expressed (you can consider the expressed to mean that the gene is active or being used) and some that are not. Regardless, all the genes an organism has are considered the genotype.
Mars' closest approach to the Earth is called opposition, and occurs roughly every 780 days.
And so it will be close and bright every two years for billions of years to come! Bottom line: Mars is bright when it and Earth are on the same side of the sun. Itâs faint when it and Earth are on opposite sides of the sun.