As of early 2023, NASA's Mars Odyssey spacecraft had beamed back over 1.2 million images and nearly 150 gigabytes of data gathered during more than 21 years in orbit around the Red Planet. That wealth of data has yielded an abundance of significant scientific knowledge about water ice on Mars, the composition and physical properties of the planet's surface, and Mars' two moons.
Historical Perspective...
In the 1500s, people believed that the Earth was the center of the universe, and everything revolved around our planet. A revolutionary idea was published in 1543 by Nicolaus Copernicus. He provided mathematical evidence for a heliocentric universe, one where the planets in the solar system revolve around the sun. This theory was formed two hundred years before the telescope was invented, using his eyes to watch the heavens. Unfortunately, Copernicus never knew what a change his theory would cause in the scientific community, as his theory was published at the end of his life, and was not widely accepted until about 100 years after his death.