For the past couple of weeks SkyView has not been able access data from the WISE archive. SkyView queries for WISE images in regions already in our cache worked fine, but users who requested a new region got back a blank image. This behavior seems to have started around June 27.
The problem arose when WISE inadvertently changed the URL’s they published the data under (using the VO Simple Image Access Protocol) to a format that was really only intended for internal use. In particular it used a non-standard port number, rather than the standard HTTP port 80. The firewall that our web servers are behind does not permit access to unregistered, non-standard ports, so our servers were unable to download new data.
The WISE team fixed the problem immediately upon being notified of it and all should be back to normal. We apologize for the time it took to discover this problem. The normal behavior requests in cached regions concealed the problem from our regular checks.