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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"

Milky Way Rising

01/12/2023

Milky Way Rising
Image Credit: José Rodrigues / NASA APOD

The core of the Milky Way is rising beyond the Chilean mountain-top La Silla Observatory in this deep night skyscape. Seen toward the constellation Sagittarius, our home galaxy's center is flanked on the left, by the European Southern Observatory's New Technology Telescope which pioneered the use of active optics to accurately control the shape of large telescope mirrors. To the right stands the ESO 3.6-meter Telescope, home of the exoplanet hunting HARPS and NIRPS spectrographs. Between them, the galaxy's central bulge is filled with obscuring clouds of interstellar dust, bright stars, clusters, and nebulae. Prominent reddish hydrogen emission from the star-forming Lagoon Nebula, M8, is near center. The Trifid Nebula, M20, combines blue light of a dusty reflection nebula with reddish emission just left of the cosmic Lagoon. Both are popular stops on telescopic tours of the galactic center. The composited image is a stack of separate exposures for ground and sky made in April 2023, all captured consecutively with the same framing and camera equipment.