NGC 6188
RA 16h 40m · Dec -48° 48′
5′

The Rim Nebula in Ara, a star-forming ridge on the edge of a giant molecular cloud, imaged from Siding Spring over two nights in the Hubble palette: SII to red, Ha to green, OIII to blue. 180 minutes total. The green cast an untreated SHO assembly produces is removed by taking only the green excess over the mean of red and blue, so the Ha structure survives but stops dominating the colour.

Emission nebula

NGC 6188

NGC 6188 · Ara
We don’t yet know how old these photons are.
HαHydrogen-alpha at 656nm. The deep red glow of ionised hydrogen and the backbone of emission-nebula and solar imaging.iTelescope T59iTelescope Planewave CDK20Siding Spring Observatory, Australia · Planewave 20-inch CDK · Corrected Dall-Kirkham astrograph · Aperture 510mm · Focal length 3411mm · f/6.8 · Camera FLI…View equipment →OIIIDoubly-ionised oxygen at 496/501nm. Teal emission from planetary nebulae and supernova remnants.iTelescope T59iTelescope Planewave CDK20Siding Spring Observatory, Australia · Planewave 20-inch CDK · Corrected Dall-Kirkham astrograph · Aperture 510mm · Focal length 3411mm · f/6.8 · Camera FLI…View equipment →SIISingly-ionised sulphur at 672nm. Deep red emission, often the third channel in the Hubble (SHO) palette.iTelescope T59iTelescope Planewave CDK20Siding Spring Observatory, Australia · Planewave 20-inch CDK · Corrected Dall-Kirkham astrograph · Aperture 510mm · Focal length 3411mm · f/6.8 · Camera FLI…View equipment →
⧉ 12 versions of this capture — pick one to see its image and log
↻ Revisited — built over 3 nights, seven nights later
  1. 1 16/09/2026 180m (H 8, O 4, S 6 x 600s) iTelescope T59
  2. 2 18/09/2026 240m (H 8, O 10, S 6 x 600s) iTelescope T59
  3. 3 23/09/2026 300m (H 8, O 10, S 12 x 600s) iTelescope T59
16/09/2026 23/09/2026 Seven nights later
Date
23/09/2026
Location
Siding Spring Observatory (remote)
Integration
300m (H 8, O 10, S 12 x 600s)
Software
PythonastropyastroalignSEPscikit-imagephotutilsAstrometry.net
Notes
Deconvolved with stars protected and the sky denoised. Green excess removed at 90 per cent and star colour neutralised at 85 per cent. Solved on 600 stars, residual 0.60 px (0.32 arcsec). Zero point 23.681, scatter 0.300 mag on 2859 stars, 4993 sources detected against 2303 in the 240 minute version. The limiting magnitude figure is NOT comparable between the two runs: it is read off a percentile band that moves with depth, so it reads 17.47 here against 17.58 there despite more than twice the detections. Source count is the honest comparison. Over the 240 minute version this adds 6 SII from 2026-09-23, taking the total to 300 minutes.
Total effort
48h over 4 nights
Moon
🌔Waxing gibbous, 89% lit
Plate solve
Centre RA
16.669367
Centre Dec
-48.795241
Field
0.6149
Pixel scale
0.5404
Orientation
95.18
Hemisphere
Southern
Also in this frame
NGC 6188NGC 6193

Catalogued objects inside the plate-solved field, nearest the centre first. Highlighted names have their own photo here.

TelescopeiTelescope T59

Where to find it

Finder chart
-49°-48°50′-48°40′-48°30′16h39m16h39m16h40m16h41m16h41m16h42mNGC 6188NGC 6193NE36.9′ x 36.9′5′

Star field and catalogued objects inside the plate-solved field, oriented to the solve. Fully offline, from the bundled star and deep-sky catalogues.

Interactive sky chart centred on 16.669367 -48.795241. Drag to pan, scroll to zoom, click a star or object to identify it. Zoom in to the plate-solved field for the DSS survey photo; zoom out for constellation figures and neighbouring catalogue objects. Fully self-hosted: the star and deep-sky catalogues and the survey image are all served from this site, so nothing external loads. Imagery: DSS2 colour (STScI / POSS-II). Constellation figures © Dominic Ford (GPLv3).

Captured remotely from · Australia
Bortle 2 · truly dark
Siding Spring Observatory · view on OpenStreetMap ↗ · Place data © GeoNames (CC BY)

Frequently asked questions

What kind of object is NGC 6188?
NGC 6188 is an emission nebula.
Which constellation is NGC 6188 in?
NGC 6188 lies in the constellation Ara.
What are the coordinates of NGC 6188?
NGC 6188 sits at right ascension 16h 40m 10s and declination −48° 47′ 43″ (J2000).
When is the best time to photograph NGC 6188?
NGC 6188 rides highest in the evening sky around May, reaching about 72° above the horizon from Siding Spring Observatory (31°S).
What else is in this frame?
The plate-solved field also contains NGC 6193.
What equipment was used to photograph NGC 6188?
This image of NGC 6188 was captured with iTelescope T59.
How much exposure time went into this image?
This image of NGC 6188 represents 300m (H 8, O 10, S 12 x 600s) + 240m (H 8, O 10, S 6 x 600s) + 180m (H 8, O 4, S 6 x 600s) of total integration time.

Comments

Leave a comment

Your email is never shown. Comments are held for moderation before they appear.