We have recently discussed the remarkable properties of the 10,000 solar mass Young Star Cluster known as Westerlund 2 in the "Observation Reports" forum:
http://www.iceinspace.com.au/forum/s...d.php?t=119363
I now present some further images of Westerlund 2, plus some images of its even more massive cousin, the star cluster which is known as Westerlund 1;
the young cluster Westerlund 1 has a total mass of at least 50,000 solar masses and it is therefore a good candidate for a young (
newly formed) globular star cluster.
I present some images made from the .fits image files of some Spitzer Space Telescope images; specifically, the near- and mid- infrared images I present are from a Spitzer infrared survey of the Milky Way called GLIMPSE:
http://irsa.ipac.caltech.edu/data/SPITZER/GLIMPSE/
It can be slow and fiddly to get infrared images of galactic and extragalactic objects from the NASA/IPAC infrared images archive (
http://irsa.ipac.caltech.edu/index.html ), and the large fits files (as much as 100 MB each) can blow your data limit, but it is worth the trouble to do this in order to obtain better images of those many Milky Way objects that are greatly obscured and dimmed by many magnitudes of extinction from the foreground screen of interstellar dust.
These highly obscured objects can be better seen in the low-extinction near-infrared and mid-infrared images, especially in the
most recent infrared imaging surveys: those made by the WISE telescope, the Spitzer Space Telescope, and the Herschel Space Observatory. [ Of these three telescopes, the Spitzer images have the highest angular resolution, though they are "science" exposures and they are not always "pretty".]
______________________
To set the scene, I display (again) the Aladin Database image of the nebula RCW 49 and the cluster Westerlund 2.
This is a composite of two Digitized Sky Survey images:
Now here is a downloaded infrared image of Westerlund 2 from the Spitzer Space Telescope. A lot more stars are seen here, even in a shallow exposure, as they are much less obscured by dust in the infrared. This image is part of the GLIMPSE survey, and I have tried here to emphasize both inner and outer parts of the cluster:
(note: the Spitzer telescope's image quality in the near-infrared is often modest, e.g. 2-4 arcsecond star images, but as a famous lady infrared astronomer once said....."I don't care if it's plastic, as long as it is in the near-infrared and I can see it".)
_____________________________
Now for a few images of the Even More Massive star cluster, Westerlund 1
Here is a DSS red image of Westerlund 1:
Here is the Digitized Sky Survey image of this cluster, from wikisky:
Now here is a near-infrared composite of J and H and K images, from the 2MASS survey:
Now here is the infrared image of Westerlund 1 from the Spitzer Space Telescope in its GLIMPSE survey (I made this .jpg from a fits file that I downloaded):
