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The Small Magellanic Cloud is a frantic star birth site. This is better seen by the ratio of the mass of neutral Hydrogen (also called HI) to the luminosity of the galaxy in blue light. This ratio is, for the Milky Way, about 0.1. For the LMC, it is 0.3 and for the SMC, it is 1, ten times that of the MW. This does not mean that the star birth ratio in the SMC is as much as ten times that of the MW, but it gives us an idea of a higher rate…
In order to better stress the reason for that, this image (a 1×2 mosaic) was taken in broadband LRGB (to give the stars a more natural color) and narrowband (Halpha and OIII). This shows that the HII regions (red color clouds) are more numerous as it can be seen by imaging it with only LRGB (see a previous, LRGB, image of the SMC here). Narrowband filters also help to stress better the OIII contribution (bluish-green clouds). In order to increase the crispness and resolution of the final image, this wide field mosaic has been enhanced by blending the higher resolution images of three objects (NGC 104, NGC 346 and MGC 456) previously taken with a CDK 20″.
Additional Information
Object
Name(s): NGC 292 and NGC 104 (47 Tuc)
Type: Barred Spiral Galaxy
RA: 00h 52m 36s
Dec: -72º 48’ 07”
Constellation: Tucana
Size (arcmin): 320×210
Magnitude: +2.3
Distance: 200,000 ly
Image
Date: 2017-08-07 thru 2017-09-01
Location: iTelescope.net, SSO near Coonabarabran, NSW Australia
Size (arcmin): 288×180
Telescope: Takahashi TOA 130 f/5.7 and Planewave CDK 20” f/6.8
Camera: SBIG STX16803 (4096x4096pix) (in both cases)
Guiding: Astrodon MonsterMOAG off-axis guider
Total exposure: 50 hours. Mosaic: 29h 50m (Ha: 13h40m; OIII: 4h10m; L: 4h: RGB: 8h) plus 20h15m (Higher Resolution images).
Processing: CCDStack, Photoshop CC 2018