Dark energy and dark matter: the mysteries of the universe

L'énergie noire et la matière noire : les mystères de l'univers

IN BRIEF Dark matter: Makes up about 25% of the universe. Dark energy: Represents about 70% of the universe. Dark matter: Has an attractive virtue, promoting clumping. Dark energy: Has a repulsive virtue, pushing celestial objects away. 95% of the universe: Formed by dark matter and dark energy. Invisible: Cannot be detected by light. Persistent … Read more

Spiral galaxies: characteristics and mysteries

Les galaxies spirales : caractéristiques et mystères

IN BRIEF Spiral galaxies: grouping of hundreds of billions of stars Structure in the shape of a disk and central bulge Formed by the collapse of hydrogen and helium clouds Spiral arms influenced by giant molecular clouds Notable examples like the Milky Way and the Andromeda Galaxy Variety of shapes: spiral, elliptical, barred, and irregular … Read more