NGC 5042 is a stunning spiral galaxy that showcases a gorgeous combination of old stars, young blue star clusters, and vivid pink HII regions—cradles of stars illuminated by massive, ephemeral stars. This Hubble Space Telescope image is the focus of astronomy enthusiasts this week.
NGC 5042 is located about 48 million light-years away in the constellation Hydra and dominates the frame of this Hubble image. A foreground star from our own Milky Way appears near the edge of the galaxy, marked by a cross-shaped diffraction spike that blends into its bright stellar environment.
To create this vivid image, Hubble observed NGC 5042 at six different wavelengths, ranging from ultraviolet to infrared. The galaxy's core glows with a warm, creamy glow, a sign of densely packed ancient stars. In contrast, its spiral arms sparkle with young blue stars scattered among bright star clusters. Beyond NGC 5042, faint, elongated yellow-orange shapes reveal more distant background galaxies, adding depth to this cosmic scene.
Perhaps the most striking feature of NGC 5042 is the bright pink clouds of gas that line its spiral arms. These shimmering clouds are called HII (pronounced "H-two") regions, and their unique color comes from hydrogen atoms ionized by ultraviolet light. If you look closely at this image, you'll see many red clouds associated with clusters of blue stars, often looking like shells around stars.
HII regions appear in expanding hydrogen gas clouds, and only hot and massive stars can produce enough high-energy light to form HII regions. Because stars capable of forming HII regions live only a few million years—a blink of an eye from the perspective of the Milky Way—this image represents a brief snapshot of life in this galaxy.
Compiled from /ScitechDaily