Captured at Al Sadeem Observatory, operated by Al Sadeem Astronomy in the United Arab Emirates
Total integration time +120 hours

What you are looking at

This is the Andromeda Galaxy (M31), the nearest big spiral to us and the heavyweight of the Local Group. With 120 hours on target, the image reveals both the glowing spiral arms of Andromeda and something very peculiar in the foreground: SDSO1.

SDSO1: a ghost with a tail

SDSO1 is not part of Andromeda at all. It is a huge bow shock nebula in our own Milky Way, born from the faded planetary nebula of the symbiotic star EG Andromedae. The shock front glows bright in OIII, arcs across the sky, and trails a 45-parsec tail that cuts across the backdrop of Andromeda.

Astronomers now call this a new stage in planetary nebula life: the ghost PN phase. The central star has dimmed but the supersonic motion through the interstellar medium keeps the bow shock shining.

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Andromeda’s own story

While the ghost PN drifts in the foreground, Andromeda is full of its own surprises.
Andromeda XXXV: the faintest known satellite dwarf of M31, as dim as MV = –5.2, poor in metals, but proof that Andromeda’s halo still hides secrets.
Hot halo: fast radio bursts passing through M31 show that it is wrapped in a giant reservoir of hot gas, maybe even linked in a bridge of baryons to the Milky Way.
Project AMIGA: a huge effort to map M31’s circumgalactic medium has revealed layers of cool, warm, and hot gas swirling around the galaxy out to hundreds of kiloparsecs.

Final thought
This field shows a dying star’s ghostly bow shock in our Galaxy painted across the living spiral of Andromeda. A mix of past and future, of fading light and ongoing star birth. A cosmic postcard from Abu Dhabi skies.