NASA’s Spitzer Space Telescope has recently shared an image of a nebula that appears like a red butterfly in space. Originally named Westerhout 40 (W40), the nebula is home to many stars.
The nebula is almost 1,400 light-years from the Sun in the constellation Serpens, about the same distance as the well-known Orion nebula.
The butterfly wings appearing in the image are giant bubbles of hot interstellar gas blowing from the hottest, most massive stars in this region. The wings-forming material is ejected by a star cluster between the wings in the image.
W40 IRS 1a is the hottest, most massive of these stars. It is located near the center of the star cluster.