The Milky Way is a spiral galaxy in
which we reside and appears in the night
sky as a glowing band.
The galaxy is on the order of 100,000 light-years
in diameter, about 1000 light-years in
thickness and has 200-400 billion stars.
Its mass is about a trillion solar masses.
The solar system is about half way between
its center and its edge.
It is the second largest galaxy in the Local Group,
the largest being Andromeda.
An orbit of the Sun around the galaxy
lasts in the range of 225-250 million years
(i.e., the galactic period aka galactic year or cosmic year).
The Milky Way's oldest stars are about 13
billion years old.
Canis Major Dwarf Galaxy
cosmic optical background (COB)
cosmic distance ladder
Council of Giants
cosmic X-ray background (CXB)
Event Horizon Telescope (EHT)
frame of reference
fast radio burst (FRB)
galactic electron density
galaxy main sequence
Galactic All-sky Survey (GASS)
globular cluster (GC)
Atlas of Galactic Nebulae (GN)
hierarchical assembly of galaxies
Hubble constant (H0)
Hubble Ultra-Deep Field (HUDF)
high-velocity cloud (HVC)
hypervelocity star (HVS)
interstellar magnetic field (ISMF)
Large Magellanic Cloud (LMC)
Local Group (LG)
local standard of rest (LSR)
luminosity distance (dL)
Local Volume (LV)
Triangulum Galaxy (M33)
solar mass (MSun)
Milky Way chemical evolution
NASA/IPAC Extragalactic Database (NED)
RR Lyrae variable
Sagittarius Dwarf Elliptical Galaxy (Sgr dE)
Sloan Digital Sky Survey (SDSS)
supermassive black hole (SMBH)
Small Magellanic Cloud (SMC)
Spitzer Space Telescope (SST)
stellar distance determination
Triangulum II (Tri II)
Two Micron All-sky Survey (2MASS)
ultra-faint dwarf galaxy (UFD)
Westerhout Radio Survey (W)
zone of avoidance (ZOA)