Sh2-124 — 1959 Hide-N-Go-Seek Champion

Sh2-124 — 1959 Hide-N-Go-Seek Champion

In 1959, American astronomer Stewart Sharpless published the second and final edition of his catalog of Galactic H II regions. Among its more than 300 entries was Sh2-124 — and apparently it has been hiding rather successfully ever since.

Located in the northern reaches of Cygnus roughly 8,500 light-years away, Sh2-124 is a large and remarkably faint emission nebula. It lies in one of the richest parts of the Milky Way, surrounded by an enormous population of foreground and background stars that can easily overwhelm the delicate nebulosity. Even today it remains a comparatively rarely imaged and little-known member of the Sharpless catalog.

Sh2-124 is an H II region — a vast cloud of hydrogen being ionized by hot young stars. The region is also associated with ongoing star formation, including embedded infrared sources hidden within its dust and gas. Its visible glow is dominated by hydrogen-alpha, while the weaker emissions and dusty structure become much more elusive.

And that is what attracted me to this field.

At first glance there almost seems to be more star field than nebula. But once you begin looking through the stars, the structure starts to emerge: faint folds of glowing gas, dark intrusions, and wispy filaments stretching through a surprisingly large and complicated cloud.

Stewart Sharpless found it well enough to put it in his catalog in 1959.

After that, it apparently went back into hiding.