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Andromeda Galaxy

The Andromeda Galaxy (M31) is the nearest major galaxy to the Milky Way, located about 2.5 million light-years away. It is a spiral galaxy similar in structure to our own.

Source: science.nasa.gov

APODs including "Andromeda Galaxy"

M33: The Triangulum Galaxy

08/07/1996

M33: The Triangulum Galaxy
Image Credit: NASA Astronomy Picture of the Day

The spiral galaxy M33 is a mid-sized member of our Local Group of galaxies. M33 is also called the Triangulum Galaxy for the constellation in which it resides. About four times smaller (in radius) than our Milky Way Galaxy and the Andromeda Galaxy (M31), it is much larger than the many of the local dwarf spheroidal galaxies. M33's proximity to M31 causes it to be thought by some to be a satellite galaxy of this more massive galaxy. M33's proximity to our Milky Way galaxy causes it to appear more than twice the angular size of the full moon, and visible with a good pair of binoculars. In the above picture, visible light is shown in red and ultraviolet light superposed in blue. Stars in M33 are the most distant ever to be studied spectroscopically.