JAXA, ESA, CSA imagery is always copyrighted, and almost always non-commercial/educational usage restricted.
All images dealing with Russian space endeavours are a big unknown. It is assumed that patches and crew portraits fall under "official state documents PD-RU-Exempt", or some sort of "PD license" under the ISS agreement, but no one is really sure. Soyuz crew portraits are even more dubious, russian launches a total unknown. Note that NASA has many folks working in Moskou and Baikonur, who DO produce free images
Visible Earth has an exception for QuickBird, SeaWiFS, OrbView and IKONOS imagery. These are NOT PD-USGov-NASA, though some of it is released as PD by their ownsers, after a set period of time.
Hubble imagery is not fully defined. It seems that ESA claims copyright on them in Europe, but with these almost certainly PD in the USA, this seems irrelevant in normal practicality. Still, due to this possible "dual"-licensing, tagging them with their own license could be useful for the future. see also
Landsat images are both PD-USGov-USGS and PD-USGov-NASA technically. since USGS does the primary management, USGS tag might be more appropriate.
SDSS (Sload digital sky survey) is non-commercial see also
NRAO images are non-commercial. NRAO is a project managed by AUI and financed (partly?) by grants of the NSF. Unlike NASA (which employs people and has it's own laboratories), the NSF only "donates" money to organizations. As such the works are not produced by an US government employee. The NRAO images are copyrighted and usage is licensed with this image policy. NRAO and NRAO partners explicitly claim copyright under a non-commercial license and the images are therefore not usable in Commons.
The key to the Chandra credits is:
Organization funding or owning the telescope/PI's institution/PI's name.
So NASA/CXC/UC Berkeley/N. Smith et al. indicates NASA ownership of the telescope, we add CXC to indicate Chandra, then the PI's institution and the PI and/team for intellectual credit. If there is only one iteration of these three categories, and NASA is the name indicating ownership of the telescope, then the image or material is public domain. The other places simply give credit for the science discovery. If the first set of three is followed by a comma, and another credit in which the owner of the telescope is not named as NASA, then you have to get permission from the other organization to use that other layer or layers of the image.