|
Designations:
|
Sharpless 142, NGC7380
|
||
|
Object Type:
|
Open Cluster and Nebulosity
|
||
|
Constellation:
|
Cepheus
|
||
|
22 hr 43.1 min
|
+58° 08 min
|
||
|
7.4 (Cluster)
|
Size:
|
||
|
Distance:
|
9,700 light-years
|
||
|
Discoverer:
|
Caroline Herschel, 1787
|
||
|
NGC 7380 (Sharpless-142) is situated about 4° from the nucleus of the
extensive Cepheus OB1
Association - an "old" star-forming region 2,000 light-years-wide and 10,000
light-years distant. Although NGC 7380 is young (between 2 and 4 million years) star formation in the
cluster has stopped or is extremely low. Indeed, Infrared Astronomical Satellite
(IRAS) data reveal 18
sources indication that stars may still be forming in the complex. NGC 7380 has 125 members of 9th
magnitude
and fainter. Most are Type O and early B stars still embedded in their natal cocoon of dust
and gas. The nebula (Sharpless 2-142) is being excited mainly by the 8.6-
magnitude
eclipsing binary DH Cepheii (HD 215835).
Color images of the region show a turbulent sea of pink gas clouds washed by waves of dark dust whose sharply chiseled crests reveal the eroding action of the region's strong stellar winds. Hydrogen-alpha light imagery of Sharpless 2-142 shows it to be composed of several bright arcuated clouds, rims, and knots interlaced with local dust lanes. Mexican astronomer Carlos Chavarria (Institute of Astronomy, UNAM, Mexico) and his colleagues not in a 1994 Astronomy and Astrophysics paper, "Sharpless 2-142 is but a 'blister' on the surface of the more extensive molecular which is seen edge on." Radio observations reveal two components to this cloud: one to the northeast, one to the southwest. The northeastern component is a 'sphere' with roughly 30 light-year-wide diameter containing about 708 percent of the cloud's mass. |
|
Telescope:
|
|
|
Focal Length:
|
1200 mm
|
|
Mount:
|
|
|
Camera
|
|
|
Guider:
|
|
|
Exposures:
|
9 15-Minute Exposures through a Hydrogen-Alpha filter.
|
|
Location:
|
Cicero, IN
|
|
Software:
|
CCDSoft for image acquisition, processed with CCDStack and Photoshop CS2
|
|
Image Automation:
|
|
