News Release Archive:

News Release 329 of 947

December 11, 2006 01:30 PM (EST)

News Release Number: STScI-2006-54

Heavyweight Stars Light Up Nebula NGC 6357

Technical facts about this news release:

About the Object
Object Name: Pismis 24, NGC 6357, Cl Pismis 24
Object Description: Open Star Cluster and Emission Nebula
Position (J2000): R.A. 17h 25m 24s.00
Dec. -34° 26' 0."0
Constellation: Scorpius
Distance: About 8,000 light-years (2,500 parsecs)
Dimensions: The width of the largest component of the release image (see "Orientation/Scale" image below) is 2.4 arcminutes (6 light-years or 1.75 parsecs).
About the Data
Data Description: This image was created from HST data from the following proposal 10602: J. Maiz-Apellaniz (Instituto de Astrofísica de Andalucía, Spain), N. Walborn and E. Nelan (STScI), N. Morrell Carnegie Institution of Washington), and V. Niemela (Universidad Nacional de La Plata); 9857: O. De Marco (American Museum of Natural History), C. R. O'Dell (Vanderbilt University), and R. Rubin (NASA Ames Research Center); and proposal 9091: J. Hester, P. Scowen, and K. Healy, (Arizona State University).
Instrument: ACS/WFC, ACS/HRC, WFPC2
Exposure Date(s): April 2002 and April 2006
Filters: F550W (V), F547M (Strömgren y), F656N (Halpha), F658N (Halpha+[N II]), F850LP (SDSS i)
About the Image
Image Credit: NASA, ESA, and J. Maíz Apellániz
Instituto de Astrofísica de Andalucía, Spain
Release Date: December 11, 2006
Color: This image is a composite of many separate exposures made by the ACS and WFPC2 instruments on the Hubble Space Telescope using several different filters. Five filters were used to sample both broad and narrow wavelength ranges. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are:
Blue: F550W (V) + F547M (Strömgren y)
Red: F656N (Halpha) + F658N (Halpha+[N II]) + F850LP (SDSS i)
Orientation/Scale: Pismis 24 and NGC 6357