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Nebula

A nebula is a giant cloud of gas (mostly hydrogen and helium) and cosmic dust situated between stars in the interstellar medium. Nebulae serve as sites of stellar birth and death—including emission nebulae that glow from ionized gas, reflection nebulae that scatter starlight, and dark nebulae that obscure background stars.

Source: science.nasa.gov

APODs including "Nebula"

Roses are Red

14/02/2026

Roses are Red
Image Credit: Keighley Rockcliffe / NASA APOD

Roses are red, nebulas are too, and this Valentine's gift is a stunning view! Pictured is a loving look at the Rosette Nebula (NGC 2237): a cosmic bloom of bright young stars sitting atop a stem of glowing hot gas. The rose’s blue-white speckles are among the most luminous stars in the galaxy, with some burning millions of times brighter than the Sun. Their stellar winds sculpt the famed rose shape by pushing gas and dust away from the center. Though only a few million years old, these massive stars are already nearing the end of their lives, while dimmer stars embedded in the nebula will burn for billions of years to come. The vibrant red hue comes from hydrogen gas, ionized by the ultraviolet light from the young stars. The rose’s blue-white center is color-mapped to indicate the presence of similarly ionized oxygen. The Rosette Nebula reminds us of the beauty and transformation woven into the fabric of the universe.