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View Full Version : Object Of The Week November 22, 2020 – NGC 1499, The California Nebula



wvreeven
November 23rd, 2020, 10:04 AM
NGC 1499, Sh2-220, The California Nebula

Emission Nebula

Constellation: Perseus

RA: 04 03 18.0
DEC: +36 25 18

Mag: about 6.0

Size: about 2.5º long

I was looking through the OOTW objects and then DeepSkyForum in general and was surprised to barely find any references to this challenging nebula! The California Nebula was discovered by E.E. Bernard in 1884 (according to Wikipedia) or 1885 (according to Atlas Of The Universe). Unfortunately that is all I could discover about its discovery.

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Source: https://astrobackyard.com/california-nebula/

It lies in the Milky Way's Orion Arm which the Sun is part of as well. The hydrogen in this cloud glows because of excitation by the nearby bright O7 star Xi Persei or Menkib. This is one of the exemplary nebulae for which UHC and especially OIII filters don't work. Instead a H-Beta filter is needed to observe this nebula visually. The nebula emits more light in H-Alpha but due to the poor response of human eyes to that wavelength, H-Beta filters work better. Due to its size and low surface brightness, very dark skies and large exit pupils are needed as well.

I am sure many of us have observed it at least once and I am curious to your observations. This APOD picture shows that the emission actually is much larger than generally seen in images and I wonder to what extend this is visible.

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Source: https://apod.nasa.gov/apod/ap190823.html

I have seen the nebula in telescopes as small as 60 mm and I suspect that it may be visible with small binoculars or possibly the naked eye as well. I have one observation logged with my good old 15 cm Newton telescope from the Netherlands. I used a 40 mm Plössl eye piece so the field of view was about 2º:

"At 25x I see a large glow when I move my telescope just north of Xi Persei. It is 2 to 3 fields of view in size and curves towards the south east. The south east end is surprisingly bright. The glow is split in two just north of Xi Persei. Some parts of the nebula are brighter than the rest. The glow is pretty faint, comparable to or slightly fainter than the Milky Way in Gemini."

Also don't forget to check out this galaxy behind the California Nebula:

http://www.deepskyforum.com/showthread.php?815-IC-2005-a-galaxy-hidden-behind-the-California-Nebula


As always,

"Give it a go and let us know!
Good luck and great viewing!"

Raul Leon
November 23rd, 2020, 12:24 PM
Hi, I have observed ngc 1499 in all three of my telescopes: 4 inch reflector, 8 inch Schmidt Newtonian and 15 inch Dobsonian, all 3 with a H Beta filter. I have never sketched it , because it's dimensions are so big.

j.gardavsky
November 23rd, 2020, 04:01 PM
Hello all,

in my observing logbook, I have 27 entries on the California Nebula, all of them through the binoculars, once as small as 7x35.
The nebula is listed by Phil Harrington in his TUBA as a binocular object.

The last observation: 14th November 2020, binoculars 10.5x70, and 15x85 with the blue(RGB)CCD filters)*:
A comfortably bright streak of light, no details at these low magnifications.

Otherwise, the nebula has been visible as a coming and fading streak of light with unaided eyes, not possible to keep, no H-Beta filters. The bright Ksi Persei has been distracting.
Reference DSOs seen with unaided eyes: Sh2-264 (Lambda Orionis Nebula) - its glow towards NNE; The Great Orion Nebula pretty bright.

)* This filter finds an increasing use when hunting the Lynds bright nebulae and some ISM and IFN.

Clear skies,
Jiri

Ivan Maly
November 24th, 2020, 02:01 AM
I haven't looked at it in a while, but it was one of my favorite objects when I observed with my old 4" F/5.5 Televue (and Lumicon 2" H-beta in Pentax XW 40 mm). Doc Werkman first showed it to me in his 80 mm Stellarvue from the summit of Spruce Knob (4800 ft) in 2007, when it was Bortle 2, and subsequently I would look at it every time from similar sites when it was well positioned. The main part of the nebula (California-shaped) had the two main bright channels and some more texture to it.

Bertrand Laville
November 24th, 2020, 09:32 AM
Hi All,

California is undoubtedly a huge target which must be observed with the widest possible field of view.
Here are two drawings made at the eyepiece of a 80 mm and 100 mm, but both with a 5 deg of fov.
Reports here: http://www.deepsky-drawings.com/ngc-1499/dsdlang/fr

Clear skies
Bertrand
http://www.deepsky-drawings.com/

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Uwe Glahn
November 28th, 2020, 09:32 AM
Interesting object, especially for smaller aperture. I noted through several small apertures:

Naked eye, NELM 7m0+
difficult and only visible with Hß filter; faint 1:2 elongated streak

8x30 binocular, NELM 6m5+
with Hß filter bright elongated glow, steadily visible

10x50 binocular, NELM 7m0+
even and steadily visible without a filter as a faint, 1:2 elongated glow; with Hß filter bright and slightly bend

2.8" Newton, 13x, NELM 7m0+
with Hß filter easy to see as an elongated glow

4" Newton, 13x, NELM 6m0+
visible even under average countryside sky; with Hß both edges and middle hole visible

4" Newton, NELM 6m5+
under good transparency of a countryside sky easy visible; with 13x (5.1°) + Hß nice framed and with 18x (3.5°) full format filling

4" refractor, 16x, NELM 7m0+
faint, structureless and elongated streak without filter; with Hß filter bright glow which is divided and shows some dark structures within the nebula

4" binocular telescope, 14x, NELM 6m5+
beside the main bright body (~2°) object shows faint extensions to the SE and NW with a stretch of around 5°

5" binocular telescope, 20x, NELM 7m0+
with an broadband nebula filter visible as a divided glow with a dark structure in its middle

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home (http://www.deepsky-visuell.de/Zeichnungen/NGC1499.htm)