1. The four poetic quotations describing Earth from space are, in order, Carl Sagan, 1973. Co uuic Connection (New York: Doubleday), p. 60; Gary Snyder, 1984 Good Wild Sacred (Madley, Hereford: Five Seasons Press), last page of unpaginated; Diane Ackerman, 1991, A Natural HL tory of the Sewed (New York: Random Flouse), p. 183; and Edgar Mitchell (astronaut), quoted in Kevin W. Kelley, ed., 1988 The Home Planet (Reading, Mass.: Addison-Wesley).
2. Quotation by James Lovelock in his 1979 Gaia: A Neira Look at Life on Earth (Oxford: Oxford University Press), p. 12.
3. The quotation by James Lovelock on the atmosphere appears in his 1979 Guai p. 10.
4. Evidence of life in martian meteorites reported in David S. McKay et al. 1996, “Search for past life on Mars: Possible relic biogenic activity in martian meteorite ÁL84001,” Science 273: 924–30. See also the summary article, pp. 864–66, of same.
5. The existence of a biosphere within Earth was proposed by Thomas Gold in his 1992 “The deep, hot biosphere,” Proceedings of the National Academy ofScience ’ 89: 6045–49. See also his forthcoming book by the same title, to be published by Copernicus in 1998.