“They call me a wizard, as if I wield magic here among the stars. Yet they don’t understand the forces at play, the light and dust spun into form by gravity’s silent hand.”
NGC7380 – Wizard Nebula – SHO (Hubble Palette)
Description
NGC 7380 is a young open cluster of stars in the northern circumpolar constellation of Cepheus, discovered by Caroline Herschel in 1787. The surrounding emission nebulosity is known colloquially as the Wizard Nebula, which spans an angle of 25′. Over the years it has earned its sorcerous nickname because of its similarity in appearance to a magician in a pointed hat.
It is extremely difficult to observe visually, usually requiring very dark skies and an O-III filter. The NGC 7380 complex is located at a distance of approximately 8500-years from the Sun, in the Perseus Arm of the Milky Way.
The cluster spans ~20 light-years (6 pc) with an elongated shape and an extended tail. Age estimates range from 4 to 11.9 million years (the blink of an eye, in cosmic terms). At the center of the cluster lies DH Cephei, a close, double-lined spectroscopic binary system consisting of two massive O-type stars. This pair are the primary ionizing source for the surrounding H II region, and are driving out the surrounding gas and dust while triggering star formation in the neighboring region.
Image Information
| Object(s) Catalog No. | NGC7380 |
| Object Type | Emission Nebula |
| Constellation | Cepheus |
| Size | 25′ |
| Magnitude | 7.2 |
| Distance | 8500 ly |
Conditions
| Date September | 2-4-10-13-14-15, 2024 |
| Astronomical Dusk: | 21h |
| Moon Age | 29 days to 12 days |
| Moon Phase | [Waning Crescent – Waxing Gibbous] |
| Temperature | Approximately 18 degree Celcius |
| Transparency | Below Average to Average |
| Seeing | Average |
| Wind | 5.4 km/h |
| Humidity | 73% |
| Sky ADU | n/a |
| Sky Flux (e/min) | n/a |
Equipment
Software
| Mount | CGEM – OnStep Retrofit |
| Imaging Scope | Modified Orion ED80T CF |
| Guiding Scope | APM 60mm Image Maste |
| Imaging Camera | ASI294M Pro |
| Guiding Camera | QHY5L-II-M |
| Additional Optics | SharpStar Field Flattener – 2.5″ |
| Filters | Baader SHO filters (7, 8, 8.5nm) |
| Acquisition | N.I.N.A. |
| Auto-Guiding | PHD2 |
| Processing | Pixinsight |
Acquisition Details
Number of files acquired: (51.4GB)
– 237 (Kept 179) Lights
– 240 Flats
– 114 Darks and Flat Darks
Total Integration Time: 22 hours
Single or Multiple Nights: 6 Nights
Start Time – Stop Time: [20h45- 2h-3h]
| Filters | L | R | G | B | Ha | OII | SII |
| Camera Temperature | -10 | -10 | -10 | ||||
| Binning | 1 | 1 | 1 | ||||
| Number of sub-frames | 123 | 63 | 51 | ||||
| Sub-frames duration (sec) | 300 | 600 | 600 | ||||
| Number of good sub-frames | 94 | 39 | 46 | ||||
| Number of Flats | 80 | 80 | 80 | ||||
| Flats Duration (sec) | 20 | 20 | 20 | ||||
| Number of Darks | 24 | 30 | 30 | ||||
| Number of Flat Darks | 30 | 30 | 30 | ||||
| Darks Duration (sec) | 300 | 600 | 600 | ||||
| Number of Bias | 0 | 0 | 0 |
Auto-Focuser Position: 2250
Autoguiding Average 0.5″
Acquisition Notes
Multiple nights with a lot of transparency variance. I dropped 25% of the frames due to various reasons (bad FWMH, eccentricity, snr, no. stars, etc.)
Processing Notes
Shooting at bin 1×1 (i.e. 47 Megapixels) creates large files. It took over 200 Gigabyte of hard disk space to produce this image.
Using GraXpert to remove gradiant and noise before chanel combination really help when applying color correction to get the proper SHO(Hubble) color.
Used an extracted luminance technique that worked well to bring out details in nebula.