Comment 1 for bug 276360

In usage, we have taken the point of view of informing the user via the color of the time-stamp of the requested image if its observation time is distant from the requested time. It may be worthwhile to post a growl-like notification when the image request time is distant from the closest available image. This can be further subdivided into two different cases - the case when the instrument is known to be inactive (e.g., MDI, SXT) and the case when the instrument is active but for some reason we don't have an available image.

For example, let's say some requests an image from 2013-01-01 from SXT. The image is shown in the viewer window with two warnings

"Warning: the difference between the requested date/time and the closest available SXT image is large."
"Warning: Yohkoh/SXT ceased operations in December 2001."

Similarly, if someone requests AIA data from 1998, the viewer window would display the following warnings"

"Warning: the difference between the requested date/time and the closest available AIA image is large."
"Warning: SDO/AIA began operations in April 2010."