Using Vacuum Technology to Cool CCDs

Imagine a CCD camera operating on a long exposure and seeing only 1 electron per pixel every 16 minutes. That equates to dark current of less than 0.000001 electrons/pixel/sec. Imagine the same camera delivering less than 1.75 electrons readout noise with minimal hot spots and blemishes while delivering a peak QE of 77%. To hit these specs it would need to be cooled significantly.