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Birthday · May 20, 2026

The Dark Wolf Nebula

May 20, 2026

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Selected image source ↗ APOD published May 20, 2026. Credit: William Vrbasso Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II). A publication-date match, not a photo taken on your date. Independent of NASA.

Behind the original result

The Dark Wolf Nebula

Original APOD · May 20, 2026 ↗

Read the original APOD for the astronomer’s explanation and full image credits. Its text is preserved in the archive as published.

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A dark wolf lies in gum. No, this isn’t a riddle! Today's image features the Dark Wolf Nebula (Sandqvist–Lindroos 17), a spooky dust cloud embedded within the Gum 55 (RCW 113) Nebula in the Scorpius constellation. While dust is a pest to us, it serves a vital role in creating the necessary conditions for stars to be born. The Dark Wolf absorbs the intense ultraviolet and visible light emitted by young stars in Gum 55 and re-emits it at longer, mainly infrared, wavelengths. This prevents the higher energy light from heating up the gas in the region. When a region of gas is cool enough, gravity takes over and causes the gas to collapse into a star. Not only does dust act as an interstellar thermostat, but it is also the meet-cute for single hydrogen atoms forming molecular hydrogen, the building block for stars. The seemingly sinister Dark Wolf is actually a harbinger of cosmic life.

Image credit: William Vrbasso Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II)

Explore May 20 in other years · 31 APOD entries, 1996–2026

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