Sh2-159 is a bright emission nebula located in the constellation of Cassiopeia. It is part of a larger region of star formation and is known for its striking colors, which are produced by ionized gases. The nebula is approximately 1,200 light-years away from Earth and spans about 30 light-years across. This nebula is often studied by astronomers to understand the processes of star formation and the dynamics of interstellar gas. Sh2-159 contains several young stars that contribute to the illumination of the surrounding gas, making it a fascinating object for both amateur and professional astronomers.