The Prawn Nebula, Hα emission (IC 4628, GUM 56, Ced 137b) (Paul Lloyd)

The Prawn Nebula, Hα emission (IC 4628, GUM 56, Ced 137b)

The Prawn Nebula is so named because the bright luminosity at its centre resembles the
arched back of a prawn, and two dark patches (lower left-hand end of this region) completes
the picture. Astronomers, however, are more prosaic and see this as a bright emission nebula
associated with hot, very young stars that are irradiating the gas cloud with UV light, causing
it to glow. The gas cloud has many sculptures and streams resulting from the pressure of the
light irradiating it. These are emphasised when only the Hα emissions are seen, as in this image.

The nebula lies some 6,000 ly from us, in the Sagittarius Arm of our Milky Way spiral galaxy.
It is estimated to be around 250 ly across, and appears ~3x the width of our Moon. It is
located at the base of the Scorpion’s tail, and can be seen with binoculars in a reasonably
dark sky.

In this image I have attempted to highlight the compex structure of the nebula, by isolating the
H-emission band. I have eliminated any stars to enhance this.

Telescope: William Optics FLT110 refractor + 1.37x Barlow (f = 1050mm)
Camera: ZWO ASI294MC Pro
Exposure: 30 x 300 sec, Optolong 7nm Hα filter
Bortle 3-4 sky, Moonless
Field of View: approx.1º 00’ x 0º 42’
Image processed and prepared in PixInsight and Photoshop Elements

Original
Final
B

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Unknown

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Status	Basic failed
Started	...
Astrometry.net job	8691077
PixInsight job	n/a
PixInsight queue size	n/a
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