Well-defined Numbers That Are Not Precisely Known
Sagan's number is the number of stars in the observable universe. It is named in honor of Carl Sagan. This number is reasonably well defined, since we know what stars are and what the observable universe is, but its value is not known with any certainty (it is presently estimated to be approximately 70 sextillion (short scale)).
Sagan's number is unrelated to the bogus sagan unit or the humorous use of the term "sagan" to denote any large quantity.
Read more about this topic: Indefinite And Fictitious Numbers
Famous quotes containing the words numbers and/or precisely:
“Old age equalizes—we are aware that what is happening to us has happened to untold numbers from the beginning of time. When we are young we act as if we were the first young people in the world.”
—Eric Hoffer (1902–1983)
“Most men would feel shame if caught preparing with their own hands precisely such a dinner, whether of animal or vegetable food, as is every day prepared for them by others. Yet till this is otherwise we are not civilized, and, if gentlemen and ladies, are not true men and women. This certainly suggests what change is to be made.”
—Henry David Thoreau (1817–1862)