In the January 2013 issue of Physics World there is an article by Steve Eales, illustrated with some remarkable images of galaxies obtained with the Herschel observatory. One, on page 31, is very appropriately captioned "Not stars; galaxies", because it looks very like star clouds, say in Sagittarius. It is a quite wonderful image that shows some 7000 galaxies; I'm told it's about four degrees on a side. If the entire celestial sphere were somehow to be imaged by Herschel in this way I figure one might say that the so observed universe would contain about 23 million galaxies. This prompts me to ask what, by comparison, is the actual estimated total number of galaxies in the observable galaxy-containing universe?