|
Designations:
|
sh2-199, IC1848 - The Soul Nebula
|
||
|
Object Type:
|
Open Cluster and Nebulosity
|
||
|
Constellation:
|
Cassiopeia
|
||
|
02 hhr 54 min 33 sec
(Epoch 2000) |
+60° 24 min 34 sec
(Epoch 2000) |
||
|
Distance:
|
2500 light years
|
||
|
Sharpless 199 / IC1848 is a dimmed diffused nebula neighboring IC1805.
Together, these two nebula are often called the Heart and Soul nebula. These nebulae are invisible with
our eyes. IC1848 has a size of 60 arc minutes in east-west and 30 minutes in north-south direction. And
it's often said that IC1848 looks like a shape of "embryo" turning its head eastward. The body of embryo
is brighter than the head, and the region of head includes two fine
open clusters
of Cr33 and Cr44
Stewart Sharpless of the U.S. Naval Observatory published his catalog of 313 HII regions and the catalog is comprehensive north of declination -27° using the Palomar Sky Survey plates in 1959. (south of declination -27°, the coverage is only partial) An H II region is a cloud of glowing gas and plasma, sometimes several hundred light-years across, in which star formation is taking place. Young, hot, blue stars which have formed from the gas emit copious amounts of ultraviolet light, ionizing the nebula surrounding them. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster such as the Pleiades. H II regions are named for the large amount of ionized atomic hydrogen they contain, referred to as H II by astronomers (H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). H II regions can be seen out to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Many famous objects are imaged by amateur astronomers who are unaware that they are part of the Sharpless (SH2) catalog. The great Orion nebula, also known as Sh2-281, and the commonly imaged Flame nebula, known as SH2-277, are some of the December favorites. Six months later in the month of June, SH2-25, which is also known as The Lagoon nebula and the North American Nebula listed in the catalog as SH2-117, are in the sky. Some of the objects that Sharpless includes are not HII nebulae at all; instead they are reflected star light off a galactic dust cloud above and below our own galaxy. This is known as Integrated Flux Nebulae which Steve Mandel (www.galaxyimages.com) is cataloging in his Unexplored Nebulae Project. There are a few Sharpless catalog numbers that fall into this, the largest labeled Sh2-178 near the North Star Polaris Source: http://www.sharplesscatalog.com/sharpless.aspx |
|
Telescope:
|
|
|
Focal Length:
|
384 mm (480 mm * 0.8X reducer)
|
|
Mount:
|
|
|
Camera
|
|
|
Guider:
|
|
|
Exposures:
|
15 10-Minute Exposures through a Hydrogen-Alpha filter used as luminance. 6 8-minute exposures through each color filter. Total exposure time (4 hours 54 minutes)
|
|
Location:
|
Cicero, IN
|
|
Software:
|
CCDSoft for image acquisition, processed with CCDStack and Photoshop CS2
|
|
Image Automation:
|
|
