Bima Sakti itu apa sih? Jelaskan dalam bahasa sunda ya

Bima Sakti atawa catang bobo (  alihbasa tina basa Latin Via Lactea, diturunkeun tina basa Yunani Γαλαξίας (Galaxias), kadang-kadang dirujuk sacara baasjan minangka "Galaksi"), mangrupa barred spiral galaxy tina Grup Lokal. Sanajan Bima Sakti sapersamiliar tina galaksi dina jagat, Galaksi miboga kapentingan husus kana kamanusaan sabab mangrupa tempatna Sistim tatasurya. Democritus (450 BC–370 BC) mimiti nyebutkeun yén Bima Sakti ngawengku béntang-béntang nu jarauh.

Ucapan "milky" asalna tina kumpulan cahaya bodas nu ngabaur, ngebat sapanjang bola langit katinggali ti Bumi, nu ngandung bentang - bentang jeung benda - benda laina nu ngalayah dina widang galaksi. The galaxy appéars brightest in the direction of Sagittarius, towards the galactic center. Relative to the celestial equator, the Milky Way passes as far north as the constellation of Cassiopeia and as far south as the constellation of Crux, indicating the high inclination of éarth's equatorial plane and the plane of the ecliptic relative to the galactic plane.The fact that the Milky Way divides the night sky into two roughly equal hemispheres indicates that the solar system lies close to the galactic plane.

The main disk of the Milky Way Galaxy is about 80,000 to 100,000 light years in diameter, about 250-300 thousand light yéars in circumference, and outside the Galactic core, about 1,000 light yéars in thickness. It is composed of 200 to 400 billion stars . As a guide to the relative physical scale of the Milky Way, if the galaxy were reduced to 130 km (80 mi) in diameter, the solar system would be a méré  2 mm (0.08 in) in width. The Galactic Halo extends out to 250,000 to 400,000 light years in diameter. As detailed in the Structure section below, new discoveries indicate that the disk extends much farther than previously thought.

The Milky Way's absolute magnitude, which cannot be méasured directly, is assumed by astronomical convention to be −20.5, although other authors give an absolute magnitude of -21.3.