Sh2-129 & Ou4 – The Flying Bat & Giant Squid Nebula

Sh2-129 & Ou4

The Flying Bat and Giant Squid Nebula

A Giant Squid in the Flying Bat


Very faint but also very large on planet Earth’s sky, a giant Squid Nebula cataloged as Ou4, and Sh2-129 also known as the Flying Bat Nebula, are both caught in this cosmic scene toward the royal constellation Cepheus. Discovered in 2011 by French astro-imager Nicolas Outters, the Squid Nebula’s alluring bipolar shape is distinguished here by the telltale blue-green emission from doubly ionized oxygen atoms. Though apparently completely surrounded by the reddish hydrogen emission region Sh2-129, the true distance and nature of the Squid Nebula have been difficult to determine. Still, a recent investigation suggests Ou4 really does lie within Sh2-129 some 2,300 light-years away. Consistent with that scenario, Ou4 would represent a spectacular outflow driven by HR8119, a triple system of hot, massive stars seen near the center of the nebula. The truly giant Squid Nebula would physically be nearly 50 light-years across.

The Flying Bat & Squid Nebula in Cepheus


Technical card


ObjectSh2-129 & Outters4
Imaging telescopeCelestron Rowe-Ackermann Schmidt Astrograph 8″
Imaging cameraZWO ASI 1600MM PRO
Mount iOptron CEM60
GuidingGuidescope 240mm, ZWO ASI 120MM
FilterBaader f/2 Highspeed H-Alpha, Baader f/2 Highspeed OIII, Baader f/2 Highspeed SII (each 2″), Baader R, G, B (2″)
AccessoriesStarizona Filter Slider,  Celestron Focus Motor for SCT
Integration54.8 hours, H-Alpha: 310×180″, OIII: 700×120″, SII: 280×180″, Red/Green/Blue each: 80×30″
Dates of recording18 nights between July and September 2020



NASA Astronomy Picture of the Day (10/07/2020)
Link to publication)

AdW Astrophoto of the Year 2020 (VdS)
Link to publication)

Shortlisted image in the Astronomy Photographer of the Year 2021 Stars and Nebulae category
Link to publication)


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