Deep Sky Object in Summer
M8, M20 (Lagoon & Trifid Nebulae in Sagittarius)


Date & Time: Aug 14 2007, from 20:01 to 20:17 JST(+0900)
Composed 4 shots with 5 minutes exposed
Optical: PENTAX 7.5cm(2.9") ED refractor with conversion lens (f=360mm, F4.8)
with IDAS LPS-P2-FF Light-pollution suppression filter
Auto-guided with TAKAHASHI EM-200 Equatorial
Digital Camera: Nikon D80 (Remodeled)
Location: Koumi town, Nagano pref.

Camera Settings: Recording Format...12bit CCD-RAW, converted to 16bit TIFF(3872×2592)
CCD Sensitivity...ISO1600




M8 (NGC6523) is a beautiful diffused nebula known as the "Lagoon Nebula", this name came from its figure that associates us a tropical island surrounded by a coral reef. This naked eye object is considered to be about 2500 light years away. There are plenty of stellar eggs, "Globules", in this reddish nebula detected as small lumps of dark cloud.
You can appreciate an open cluster of NGC6530 being on top of M8, the contrast with the nebula would be splendid. Actually the cluster is lying much farther than M8. And the very fine reddish nebula of IC1274-5 can be photographed like the diluted red ink around east of M8 under the sufficient clear and dark sky.
M20 (NGC6514), "The Trifid Nebula", is another delight in the Milky Way of Sagittarius, but visible only with larger scopes. Three Dark lanes devide this nebula into three parts, familiar on photographs. Distance is about 2200 light years.
These vast clouds are brightening by activated hydrogen molecules receiving energy from stars inside.
And this image includes a small open cluster of M21, found about 40 arc minutes northeast of M20. The cluster has a diameter of 10 arc minutes and contains about 50 fine member stars, can be enjoyed only with binoculars.

   To image of Close-up of M8
   To image of Close-up of M20
   To image of Rendezvous of M8 and Mars in 2001
   To image of Rendezvous of M8 and Mars in 2003

⇒ Display the spectral profile of M8 (in new window)
⇒ Display the spectral profile of M20
(in new window)

M8 (NGC6523) / Diffused Nebula, type 1 E
R.A.18h 03m 48.0s (2000.0)
Dec.-24° 23' 00" (2000.0)
Apparent Size60×35'
Real Size44×26 light yrs.
Magnitude6.0
Distance2500 light yrs.
Other IDsIC1271, LBN25
M20 (NGC6514) / Diffused Nebula, type 1 E+R
R.A.18h 02m 18.0s (2000.0)
Dec.-23° 02' 00" (2000.0)
Apparent Size29×27'
Real Size18×17 light yrs.
Magnitude9.0
Distance2200 light yrs.
Other IDsLBN27
M21 (NGC6531) / Open Cluster, type d, III 1 p n
R.A.18h 04m 42.0s (2000.0)
Dec.-22° 30f00" (2000.0)
Apparent Size10'
Real Size17 light yrs.
# of Stars18
Magnitude6.5
Distance2960 light yrs.




Wide field around Lagoon Nebula


Copyright(c) 2007 by Naoyuki Kurita, All rights reserved.
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