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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"

Orion's Treasures over Snowy Mountains

27/01/2026

Orion's Treasures over Snowy Mountains
Image Credit: Włodzimierz Bubak; Text: Ogetay Kayali (MTU) / NASA APOD

Rising over a frozen valley in the Tatra Mountains, the familiar stars and nebulas of Orion dominate this wide-field nightscape. The featured deep photo was taken in southern Poland's highest mountain range last month, where dark skies and alpine terrain combined to reveal both Earth's rugged beauty and the structure of our galaxy. Above the snowy mountains, Orion's bright belt stars anchor a region of glowing interstellar clouds. The Great Orion Nebula, a vast stellar nursery visible even to the unaided eye, shines near the center of the scene. Surrounding it is the enormous arc of Barnard's Loop, a faint shell of ionized hydrogen gas spanning much of the constellation. To the left, the round Rosette Nebula glows softly, while the grayish Witch Head Nebula hovers to the right, illuminated by nearby starlight. Near the top, the orange supergiant Betelgeuse marks the hunter's shoulder.