“They wonder how long I’ll last, how long I’ve been burning. And they never see how brief their existence is in the expanse of this glow. I’ve seen planets born and die in the blink of a cosmic eye.”
Image IC1805 – Heart Nebula – SHO (Hubble Palette)
Description
The Heart Nebula (also known as the Running Dog Nebula, Sharpless 2-190) is an emission nebula, 7500 light years away from Earth and located in the Perseus Arm of the Galaxy in the constellation Cassiopeia. It was discovered by William Herschel on 3 November 1787. It displays glowing ionized hydrogen gas and darker dust lanes.
The Heart Nebula is also made up of ionized oxygen and sulfur gasses, responsible for the rich blue and orange colors seen in this narrowband image. The shape of the nebula is driven by stellar winds from the hot stars in its core. The nebula also spans almost 2 degrees in the sky, covering an area four times that of the diameter of the full moon.
Image Information
| Object(s) Catalog No. | IC1805 |
| Object Type | Emission Nebula |
| Constellation | Cassiopeia |
| Size | 150′ x 150′ |
| Magnitude | 18.3 |
| Distance | 7,500 ly |
Conditions
| Date | October 21st , 2024 |
| Astronomical Dusk: | 20h40 |
| Moon Age | 17.9 days |
| Moon Phase | Waxing Gibbous (89.4% illumination) |
| Temperature | 17.43 Celcius |
| Transparency | Average |
| Seeing | Average |
| Wind | 18.5 km/h |
| Humidity | 67% |
| 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 | Antlia SHO 3nm Pro filters |
| Acquisition | N.I.N.A. |
| Auto-Guiding | PHD2 |
| Processing | Pixinsight |
Acquisition Details
Number of files acquired: 260 (22.6 GB)
– xx (Kept xx) Lights
– xx Flats
– xx Darks and Flat Darks
Total Integration Time: x hours
Single or Multiple Nights: 1 Nights
Start Time – Stop Time: [20h30 – 2h-3h]
| Filters | L | R | G | B | Ha | OII | SII |
| Camera Temperature | -10 | -10 | -10 | ||||
| Binning | 1 | 1 | 1 | ||||
| Number of sub-frames | 36 | 9 | 9 | ||||
| Sub-frames duration (sec) | 300 | 600 | 600 | ||||
| Number of good sub-frames | 36 | 9 | 9 | ||||
| Number of Flats | 30 | 20 | 20 | ||||
| Flats Duration (sec) | 20 | 20 | 20 | ||||
| Number of Darks | 30 | 20 | 20 | ||||
| Number of Flat Darks | 30 | 30 | 30 | ||||
| Darks Duration (sec) | 300 | 600 | 600 | ||||
| Number of Bias | 0 | 0 | 0 |
Auto-Focuser Position: 3075
Autoguiding Average 0.52″
Acquisition Notes
100% Automated and unattended acquisition. Zero image rejection.
Processing Notes
The narrowband color calibration can be tricky to get right. A lot of magenta remains after NarrowBandNormalization. I have to invert the image and apply SCRN to remove it. At this point, it is more art than science.