“Their fragile planet spins under a thin veil of air, and still they imagine they own the cosmos. They forget that their world is but a flicker in the vastness of this light.”
Image NGC1499 – California Nebula – SHO (Hubble Palette)
Description
The California Nebula is an emission nebula located in the constellation Perseus. Its name comes from its resemblance to the outline of the US State of California in long exposure photographs. It is almost 2.5° long on the sky and, because of its very low surface brightness, it is extremely difficult to observe visually. It lies at a distance of about 1,000 light years from Earth. Its fluorescence is due to excitation of the Hβ line in the nebula by the nearby prodigiously energetic O7 star, Xi Persei.
By coincidence, the California Nebula transits in the zenith in central California as the latitude matches the declination of the object.
Image Information
| Object(s) Catalog No. | NGC1499 |
| Object Type | Emission Nebula |
| Constellation | Perseus |
| Size | 2.5 degree wide |
| Magnitude | 6 |
| Distance | 1,000 ly |
Conditions
| Date | November 14th , 2024 |
| Astronomical Dusk: | 17h33 |
| Moon Age | 13.42 days |
| Moon Phase | Waxing Gibbous (98% illumination) |
| Temperature | -2 Celcius |
| Transparency | Below Average |
| Seeing | Below Average |
| Wind | 11 km/h |
| Humidity | 69% |
| 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: 127 (22.6 GB)
– 127 (Kept 117) Lights
– 90 Flats
– 50 Darks and Flat Darks
Total Integration Time: 9.75 hours
Single or Multiple Nights: 2 Nights
Start Time – Stop Time: [20h – 2h-3h]
| Filters | L | R | G | B | Ha | OII | SII |
| Camera Temperature | -10 | -10 | -10 | ||||
| Binning | 1 | 1 | 1 | ||||
| Number of sub-frames | 68 | 14 | 36 | ||||
| Sub-frames duration (sec) | 300 | 300 | 300 | ||||
| Number of good sub-frames | 58 | 14 | 34 | ||||
| Number of Flats | 30 | 30 | 30 | ||||
| Flats Duration (sec) | 20 | 20 | 20 | ||||
| Number of Darks | 20 | 20 | 20 | ||||
| Number of Flat Darks | 30 | 30 | 30 | ||||
| Darks Duration (sec) | 300 | 300 | 300 | ||||
| Number of Bias | 0 | 0 | 0 |
Auto-Focuser Position: 2589
Autoguiding Average 0.54″
Acquisition Notes
100% Automated and unattended acquisition over two nights. First night was interrupted by clouds around 1h30.
Processing Notes
Should have captured more OII data to bring the blues out more in the final image.