Tejút

Tejút is the Hungarian name for the Milky Way, the galaxy that contains the Solar System. The word combines tej (milk) and út (road or way), referring to the Milky Band visible across the night sky.

The Milky Way is a barred spiral galaxy in the Local Group. It comprises a central bulge, a bar, a disk with spiral arms, and a dark matter halo. The visible disk spans about 100,000 light-years in diameter and is about 1,000 light-years thick. The Solar System lies in the Orion Arm, roughly 27,000 light-years from the galactic center.

The galactic center hosts a supermassive black hole, Sagittarius A*, with an estimated mass of about 4 million solar masses. The galaxy contains hundreds of billions of stars, as well as vast amounts of gas and dust that fuel star formation, primarily in the spiral arms; older stars populate the bulge and halo. A dark matter halo surrounds the galaxy.

Observationally, streams of stars and gas in infrared and radio wavelengths reveal structure because our view from inside the disk is obscured by dust; the Milky Way is seen as a cloudy band across the sky.

The Milky Way is gravitationally bound within the Local Group and is approaching Andromeda. In several billion years, the two galaxies are expected to merge, forming a larger galaxy. The galaxy rotates, with the Sun orbiting the center at about 220 kilometers per second.