Sagan (number)

A Sagan is a humorous unit of measurement equal to at least 4 billion.

The unit is derived from the phrase "billions and billions (of stars)", frequently attributed to the American astronomer Carl Sagan. The lower bound of a number conforming to the constraint of "billions and billions" must be two billion plus two billion, or four billion.

Assuming one uses the short scale definition for billion, there are nearly 100 Sagan (400,000,000,000) stars in the Milky Way galaxy.

It is important to note, however, that even though many believe Sagan used the phrase "billions and billions" in reference to the number of stars in the galaxy, Sagan himself claims never to have used the phrase, instead opting for the simpler phrase "billions of stars". In fact, it was actually Johnny Carson who popularized the phrase through his occasional impersonation of Sagan throughout his career. Sagan, however, seems to have had a sense of humor about the myth, as he titled his final book "".

ee also

*Indefinite and fictitious large numbers

References

* Carl Sagan, "", Random House, 1997.