On the picture in “Galactic bull’s-eye” (SN: 9/24/11, p. 10), I
am quite puzzled. Do my eyes deceive me, or is there another
bull’s-eye galaxy behind the first, located at the 1 o’clock
position? How is this possible? Are these strange objects
magically clustered along some line pointing towards us? Jeff
Brewer, Newton Centre, Mass. It is peculiar that another ring-
galaxy–like object would appear in the background, and in fact
the Hubble Heritage Team noted its odd appearance. It’s
possible, but not probable, that the object is another Hoag...
(p. 31) Lumpy lunar illusion Are you folks aware of a phenomenon
based on the universal expectation that objects are illuminated
by light coming from above? Several startling optical illusions
are based on this quirk of the mind. For example, the sharp moon
map in “Orbiter delivers sharp moon map” (SN: 7/30/11, p. 12)
makes the moon look like it is covered with big bumps! Turn the
page upside down, and voila — the bumps turn into craters. Jeff
Brewer, Newton, Mass. Coun