Illustration of our galaxy, the Milky Way seen obliquely, with the arms and the central bar in their approximate known locations. There are four major arms and one arm fragment (Orion-Cygnus or Local) where the Sun is found. In the annotated version of this image, the yellow dot indicates the position of the Solar System about 25000 ly from the galactic core. The Norma and Outer arms are in fact the same, but the two names refer to different parts of it. The same is true of the so-called 3kpc (3 kilo-parsec) arm, which further out becomes the Perseus arm.

An image of the spiral arms of the Galaxy


Astronomers might have discovered component of a never-before-seen arm of the Milky Way galaxy. This big stream of gas – called Cattail as a result of its lengthy, slim form – is the biggest and also most far-off gas filament ever before found in our galaxy.

Keping Qiu at Nanjing College in China and also his associates discovered one end of Cattail making use of the Five-hundred-meter Aperture Round radio Telescope (QUICKLY) in China. They after that browsed information from the HI4PI study, an all-sky look for hydrogen gas, …