Astronomy Picture of the Day—20190117

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2019 January 17

TheHeart and Soul Nebulas

ImageCredit & Copyright: Mario Zauner

Explanation:Is the heart and soul of our Galaxy located in Cassiopeia? Possibly not, butthat is where two bright emission nebulas nicknamed Heart and Soul can befound. The Heart Nebula, officially dubbed IC 1805 and visible in the featuredimage on the bottom right, has a shape reminiscent of a classical heart symbol.The Soul Nebula is officially designated IC 1871 and is visible on the upperleft. Both nebulas shine brightly in the red light of energized hydrogen. Alsoshown in this three-color montage is light emitted from sulfur, shown inyellow, and oxygen, shown in blue. Several young open clusters of stars arevisible near the nebula centers. Light takes about 6,000 years to reach us fromthese nebulas, which together span roughly 300 light years. Studies of starsand clusters like those found in the Heart and Soul Nebulas have focused on howmassive stars form and how they affect their environment.