Assessment of Planetary Protection Requirements for Spacecraft Missions to Icy Solar System Bodies

Questions? Call 800-624-6242

About | Ordering | New

LoginRegister

| Items in cart [0]

PAPERBACK
price:$43.00
add to cart

Rights & Permissions

Free PDF Access

Free Resources

Related Titles

Assessment of Planetary Protection Requirements for Spacecraft Missions to Icy Solar System Bodies (2012)
Space Studies Board (SSB)

Citation Manager Export the bibliographic data for this book in your chosen format
Web Search Builder Use this book's key terms to search within this book, across our collection, or across the Web.
Skim This Chapter Skim this chapter and use this chapter's key terms to search within this book.
Reference Finder Paste in your own text to find books that relate to your topic.

Citation Manager

Committee on Planetary Protection Standards for Icy Bodies in the Outer Solar System, Space Studies Board, Division on Engineering and Physical Sciences, National Research Council. "5 Microbial Metabolism and Physiology." Assessment of Planetary Protection Requirements for Spacecraft Missions to Icy Solar System Bodies. Washington, DC: The National Academies Press, 2012.

Please select a format:

Page
44


E-mail Share on facebook Facebook Share on delicious Delicious Share on stumbleupon Stumble Share on twitter Twitter More Sharing ServicesMore

The following HTML text is provided to enhance online readability. Many aspects of typography translate only awkwardly to HTML. Please use the page image as the authoritative form to ensure accuracy.

TABLE 5.1 Examples of Electron Donors or Acceptors for Life in Icy Bodies Both Inferred and Measured in Past Work


	Europa	Comments	Enceladus	Comments	Titan	Comments

Electron Donors (observed)

Organics	Detected on surface of Callisto, Ganymede Reference a	Expected on the surface. Interior unknown	Organic compounds Reference j Size of some known; structures not known	Methane and other organics detected in the plume.	Organics and methane Reference l and m suggested as a source of energy for organisms by references n and o	Surface organics from hydrocarbon cycle

Hydrogen	n/a	n/a	n/a	n/a	Reference o

Electron Donors (suggested in literature as plausible candidates)

Hydrogen	Reference b		Reference k

Electron Acceptors (observed)

Oxygen	Observed on surface Reference c	Interior unknown

CO/CO2	CO2 on surface Reference d		Reference j	Observed in plume; CO and N2 peaks cannot be differentiated	Trace quantities of CO2 observed Reference o

SO2	Reference e

Electron Acceptors (suggested)

Sulfur	Sulfate inferred on surface Reference f and g Elemental sulfur also suggested Reference h	Interior unknown

Fe3+, other metals	Fe3+, other metals Reference b, i	Fe3+, other metals depends on connection with silicate core

NOTE: Comments are provided as caveats and context.

a K.P. Hand, C. Chyba, J.C. Priscu, R.W. Carlson, and K.H. Nealson, Astrobiology and the potential for life on Europa, pp. 589-630 in Europa (R. Pappalardo, W. McKinnon, and K. Khurana, eds.), University of Arizona Press, Tucson, Ariz., 2009.

b D. Schulze-Makuch and L.N. Irwin, Energy cycling and hypothetical organisms in Europa’s ocean, Astrobiology 2:105-121, 2002.

c J.R. Spencer and W.M. Calvin, Condensed O2 on Europa and Callisto. Astronomy Journal 124:3400-3403, 2002.

d K.P. Hand, R. Carlson, and C.F. Chyba, Energy, chemical disequilibrium, and geological constraints on Europa, Astrobiology 7:1006-1022, 2007.

e A.L. Lane, R.M. Nelson, and D.L. Matson, Evidence for sulfur implantation in Europa’s UV absorption band, Nature 292:38-39, 1981.

f T.B. McCord, G.B. Hansen, F.P. Fanale, R.W. Carlson, D.L. Matson, T.V. Johnson, W.D. Smythe, J.K. Crowley, P.D. Martin, A. Ocampo, C.A. Hibbitts, J.C. Granahan, and the NIMS Team, Salts on Europa’s surface detected by Galileo’s Near Infrared Mapping Spectrometer, Science 280:1242-1245, 1998.

g R.W. Carlson, R.E. Johnson, and M.S. Anderson, Sulfuric acid on Europa and the radiolytic sulfur cycle, Science 286:97-99, 1999.

h R.W. Carlson, W.M. Calvin, J.B. Dalton, G.B. Hansen, R.L. Hudson, R.E. Johnson, T.B. McCord, and M.H. Moore, Europa’s surface composition, pp. 283-327 in Europa (R. Pappalardo, W. McKinnon, and K. Khurana, eds.), University of Arizona Press, Tucson, Ariz., 2009.

i E.J. Gaidos, K.H. Nealson, and J.L. Kirschvink, Life in ice-covered oceans, Science 284:1631, 1999.

j J.H. Waite, Jr., M.R. Combi, W.-H. Ip, T.E. Cravens, R.L. McNutt, Jr., W. Kasprzak, R. Yelle, J. Luhmann, H. Niemann, D. Gell, B. Magee, G. Fletcher, J. Lunine, and W.-L. Tseng, Cassini ion and neutral mass spectrometer: Enceladus plume composition and structure, Science 311:1419-1422, 2006.