Spiral galaxies may consist of several distinct components:
• A flat, rotating disc of stars and
• A central stellar … See more

The pioneer of studies of the rotation of the Galaxy and the formation of the spiral arms was Bertil Lindblad in 1925. He realized that the idea of stars arranged permanently in a spiral shape was untenable. Since the angular sp… See more

Before it was understood that spiral galaxies existed outside of our Milky Way galaxy, they were often referred to as spiral nebulae, due to Lord Rosse, whose telescope Leviathan was the first to reveal the spiral st… See more

The Milky Way was once considered an ordinary spiral galaxy. Astronomers first began to suspect that the Milky Way is a barred spiral galaxy in the 1960s. Their suspicions were confirmed by Spitzer Space Telescope observations … See more

• Andromeda Galaxy – Barred spiral galaxy in the Local Group
• Milky Way – Galaxy containing the Solar System
• Pinwheel Galaxy – Galaxy in the constellation Ursa Major… See more