Update: Images are flowing again, thanks to everyone for their patience.
The SDO HMI/AIA data distribution system is undergoing some emergency repairs, and image updates from sdo.gsfc.nasa.gov have been suspended. SDO personnel are diagnosing the problem and it is not clear how long the outage will last. Data from SDO/EVE, including SAM images, will continue to be available during the outage.
We are sorry for any inconvenience.