Deep Sky Object in Winter
M46 & M47 (Open Clusters in Puppis)
|Date & Time: ||Dec 23 2006, from 27:57 to 28:27 JST(+0900)
|Composed 4 shots with 10 min. exposed|
|Optical: ||PENTAX 7.5cm(2.9") ED refractor with conversion lens (f=360mm, F4.8)
|with IDAS LPS-P1 Light-pollution suppression filter|
|Auto-guided with TAKAHASHI JP Equatorial
|Digital Camera: ||Nikon D70 (remodeled)
|Location: ||Ooizumi, Hokuto city, Yamanashi pref.
|Camera Settings: ||Recording Format...12bit CCD-RAW, converted to 16bit TIFF(3008×2000)|
This picture shows two open clusters about 13 degrees east of Sirius (alpha CMa),
and with an interval of about 1.5 degree between them.
East Side one is M46 (NGC2437), and another one is M47 (NGC2422).
Scenery of those are extremely contrary, to say,
M46 consists of plenty of fine stars, but M47 is the brighter and sparse, includes several fifth magnitude stars.
|Planetary Nebula NGC2438|
seen in M46
Distances of M46 and M47 are about 5930 and 3740 light years respectively, they have no relation each other in the Galaxy space,
we can appreciate these two in the almost same field by chance.
And a left image shows a tiny planetary nebula of NGC2438 floating in M46 with a diameter of about 68".
The nebula is a remnant of star emitting gaseous matter in front of M46.
|M46 (NGC2437) / Open Cluster, type f, II 2 r|
|R.A.||07h 41m 47.9s (2000.0)|
|Dec.||-14° 49' 00" (2000.0)|
|Real Size||42 light yrs.|
|# of Stars||100|
|Distance||5930 light yrs.||
|M47 (NGC2422) / Open Cluster, type d, I 3 m|
|R.A.||07h 36m 36.0s (2000.0)|
|Dec.||-14° 30' 00" (2000.0)|
|Real Size||27 light yrs.|
|# of Stars||30|
|Distance||3740 light yrs.|