From previous readings of James Michener's novel <Space> I was familiar with fervent admiration for Norton's Star Atlas in it, but only last night did I realize later mentioned is Allen's Astrophysical Quantities, known as A.Q., the Green Book, the astronomer's bible. The author, C.W. Allen merited an extraordinary 8-page obituary in 1987 in the Quarterly Journal of the Royal Astronomical Society. His last, 3rd edition 1973 revision, in contrast to the 2001 4th edition by 90 contributers, is a marvel of physical insight and interconnections requiring at most only high-school-level math or its terminology, whereas the 4/e has much calculus and advanced math, though this latter is a good successor once you are thoroughly familiar with the 3/e. Both editions are now dated to some extent, though the 1973 version well retains some of the flair and mystique of the nights when optical astronomy from Earth's surface held undisputed sway.