The Tarantula Nebula or 30 Doradus, is located in a nearby satellite galaxy, the Large Magellanic Cloud (LMC). This region is an active H II area, extremely luminescent, and is located around 160,000 light-years from Earth. To give a little perspective, if this object were to be relocated at an equivalent distance as the Orion Nebula, it would cast visible shadows. (Time to call out the Volgon Constructor Fleet). The Tarantula Nebula is more than 1000 light-years in diameter and is the brightest and most energetic star-forming region in the Local Group of galaxies.

Recently I processed an object NGC1968, which is located in the LMC as well. (This data set was made available for The Astro Imaging Channel workshop) I couldn't help but notice the many similar properties between these two objects — specifically the large about of bright blue stars located within the fields of both images. Their colouring was similar in the RGB component of the images. Both contain an extremely tight luminescent core. I created four different renditions for The Astro Imaging Channel as an experiment to see what each combination of filters would yield. This exercise helped developed a few ideas in how I might approach this data set and attempt to create an interesting rendition of the Tarantula Nebula. Hopefully, I didn't go too far.

The nebula is situated on the leading edge of the LMC where ram pressure is stripping, and compression with the interstellar medium is creating an incredibly twisted and contorted object with incredible dynamic range.

My goals were to create an image that hopefully retains the traditional RGB colour look about it, and reveal that wonderful contrast of small details found in narrowband images. The image is a combination of “Traditional RGB” and “Narrowband Imaging”. I do like stars, and this is definitely a dense starfield. I wanted to retain the amazing array of stars and their colours in the field. Hopefully, the result is not too distracting. The dense concentration of so many blue stars was another feature I wanted to retain.

The bottom left is interesting. There is a nice transition into subtle Dark Nebula, and the stars begin to look like something we see when imaging near our own galactic centre with that reddish hue starting to appear.

The most difficult part of the image was the white columns. No matter what I did in the RGB space, they just didn't seem to have much colour. The ADU values indicated that they were not saturated at all. In fact, they ranged for the most part around 6000-15000 ADU. This would suggest if colour were present, it should present itself with these values fairly easily. So I followed the numbers and went with that. The OIII component was introduced into the blue channel, while the Ha and SII were introduced into the green and red channels. Together, the total exposure is just over 72 hours, both colour and narrowband combined.

Thanks for looking.

Terry



Equipment Details:

•10 Inch RCOS fl 9.1

•Astro Physics AP-900 Mount

•SBIG STL 11000m

•FLI Filter Wheel

•Astrodon LRGB Filters

•Baader Planetarium H-alpha 7nm Narrowband-Filter

•Baader Planetarium OIII 8.5nm Narrowband-Filter

•Baader Planetarium SII 8.0nm Narrowband-Filter

Exposure Details

•Red 56X450 2X2

•Green 35X450 2X2

•Blue 25X450 2X2

•Lum 48X900

•Lum 65X100

•Ha 39X900

•SII 72X900

•OIII 66X900