NGC 3576, the nebula on the right, is a giant HII region in the constellation of Carina  about 9,000 light years from Earth.  Chandra showed many X-Ray point sources that are young  massive stars hidden from site within the dark clouds. They are shredding the clouds apart due to  their hot winds. It is also known as Gum38aj and forms the western part of RCW57.

The nebula on the left is NGC 3603. The Hubble Space  Telescope presents a detailed image of NGC 3603 showing that it contains one of the most massive young  clusters in the Milky Way. It is further away from Earth at ~20,000 light years compared to  NGC3576, even though they look like close neighbors in the image above.  It is located at RA  11h 11m 48s and DEC -61d 23m

Color mapping using the Hubble palette:  R = SII, G = H-a and B = OIII.