The Helix Nebula

One of the largest planetary nebula, with an apparent diameter about half the size of the Moon, the Helix Nebula is named after it’s double ringed 3D appearance.  

I’ve seen far better images than my modest unguided  23 minutes exposure and they often resemble a human eye. For some quaint reason a lot of folks refer to the Helix as “The Eye of God”, which is, of course, quite ridiculous. If there were an all-seeing god she wouldn’t have a single human eye would she?   🤨

I recall a local newspaper publishing a reader’s photo of a cloud formation which resembled a human. Of course the reader claimed it was actually God. Then there was the reader who sent in a picture of a sundog – and the paper published his claim that he had captured an alien mothership with his camera…..

It’s natural to see faces and other objects in the sky – but I reckon some folks get carried away with their goofy explanations.


This image and the next one I will be posting were taken on the first of two clear observing nights four days apart with Macarthur Astronomical Society. They were the last sessions before the dreaded daylight saving begins next Sunday here, severely curtailing astronomers observing sessions for the next six months. Next time I see the NSW Premier, I’ll be telling her I want the clocks put back an hour instead of forward.

The second of those two nights was totally unproductive. I experienced guiding errors, alignment errors and a catastrophic dew management failure. I think I now know why I had guiding problems – and maybe that caused the misalignment and maybe the low battery voltage caused the dew heaters to fail which maybe caused the guiding to play up which maybe messed up the alignment which…… you get the picture.

Or maybe each one was just human error.  🥴

The two things I did confirm from this disaster are:  1. always check the batteries are functioning normally; and  2. once a heavy dew builds up on the telescope’s objective lens at 3°C and I don’t happen to have a hair dryer and 240V handy, then I might as well hit the road!


Object Details:

Designation:    NGC 7293, Caldwell 63
Constellation: Aquarius
Visual magnitude:  +7.6
Apparent size:  14.7′ x 12′
Diameter:   3.4 light years.
Distance:   790 light years.
Altitude during exposure:  63° above Eastern horizon.
Astrometry:   Astrometry.net


No need to read the technical stuff:

Image:

Exposure:   24 x 58 sec =  23 min.
Gain:  250
Date:  2019-09-24
Location:  semi-dark rural.
Conditions:  clear
Moon: no

Processing:

Image acquisition:  SharpCap.
Method: Live stacked.
Darks: 6x
Image post-processing:  GIMP.
Cropping:  yes
Sky:    0.29 e/pixel/s .

Gear:

Telescope: SkyWatcher Esprit  Type: 120ED triplet refractor
Focal: 840 mm F/7 Mount: SkyWatcher EQ6-R Pro
Camera: ZWO ASI 071 MC Pro
Type: CMOS 28.4mm 16 Mpx
Optical aids: Flattener: Y; filter: LP Guiding: No
Polar aligning: QHYCCD PoleMaster Polar Error: 00’ 38”

Geek Log:

[ZWO ASI071MC Pro]
Debayer Preview=On
Pan=0
Tilt=0
Output Format=FITS files (*.fits)
Binning=1
Capture Area=4944×3284
Colour Space=RAW16
Hardware Binning=Off
Turbo USB=40
Flip=None
Frame Rate Limit=1 every 4 seconds
Gain=250
Exposure=58
Timestamp Frames=Off
White Bal (B)=50
White Bal (R)=53
Brightness=16
Temperature=-20.6
Cooler Power=99
Target Temperature=-20
Cooler=On
Auto Exp Max Gain=300
Auto Exp Max Exp M S=30000

Auto Exp Target Brightness=100
Mono Bin=Off
Anti Dew Heater=Off
Banding Threshold=35

Banding Suppression=0
Apply Flat=None
Subtract Dark=C:\Users\Roger\Desktop\SharpCap Captures\darks\ZWO ASI071MC Pro\RAW16@4944×3284\58.0s\gain_250\dark_6_frames_-19.8C_2019-09-24T10_16_49.fits
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.5
#White Point
Display White Point=1
TimeStamp=2019-09-24T11:33:50.3516561Z
SharpCapVersion=3.2.6086.0
TotalExposure(s)=1392
StackedFrames=24

 

Image © Roger Powell

2 Comments

  1. Funny, I’m looking forward to the upcoming daylight savings switch here in the North, as it means not having to wait hours for the sky to darken here! It will be well past Sunset by 6pm for the next few months. “Orion Season,” my favorite season.

    Liked by 1 person

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