🌌 Galaxies & The Milky Way
Our universe contains over 2 trillion galaxies. Explore the cosmic cities of stars — from our own Milky Way to giants billions of light-years away.
The Milky Way Galaxy
A barred spiral galaxy 105,700 light-years across, home to 100–400 billion stars — and one very ordinary yellow star called the Sun with its tiny family of planets.
🗺️ Structure of the Milky Way
Central Bar & Bulge
A bright bar of stars at the centre surrounded by an older, denser bulge. Contains Sagittarius A*, our 4-million-solar-mass black hole.
Spiral Arms
Four major arms (Perseus, Sagittarius, Centaurus, Outer) wind outward. Our Solar System sits in a minor arm called the Orion Spur.
Thin & Thick Disc
The main flat disc is ~1,000 light-years thick (thin disc) wrapped in an older, thicker disc of ancient stars about 3,400 light-years thick.
Stellar Halo
A vast, spherical cloud of old stars and globular clusters stretching over 200,000 light-years around the galaxy, mostly invisible dark matter.
🔭 Types of Galaxies
🌠 Galaxy Explorer
📐 Scale of the Universe
* Bar sizes are illustrative log-scale comparisons, not exact.