Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2023 Aug 11;13(8):1726.
doi: 10.3390/life13081726.

A Review on Hypothesized Metabolic Pathways on Europa and Enceladus: Space-Flight Detection Considerations

Jessica M Weber  1 , Theresa C Marlin  1 , Medha Prakash  1 , Bronwyn L Teece  1 , Katherine Dzurilla  1 , Laura M Barge  1
Affiliations
Review

A Review on Hypothesized Metabolic Pathways on Europa and Enceladus: Space-Flight Detection Considerations

Jessica M Weber et al. Life (Basel). .

Abstract

Enceladus and Europa, icy moons of Saturn and Jupiter, respectively, are believed to be habitable with liquid water oceans and therefore are of interest for future life detection missions and mission concepts. With the limited data from missions to these moons, many studies have sought to better constrain these conditions. With these constraints, researchers have, based on modeling and experimental studies, hypothesized a number of possible metabolisms that could exist on Europa and Enceladus if these worlds host life. The most often hypothesized metabolisms are methanogenesis for Enceladus and methane oxidation/sulfate reduction on Europa. Here, we outline, review, and compare the best estimated conditions of each moon's ocean. We then discuss the hypothetical metabolisms that have been suggested to be present on these moons, based on laboratory studies and Earth analogs. We also detail different detection methods that could be used to detect these hypothetical metabolic reactions and make recommendations for future research and considerations for future missions.

Keywords: Enceladus; Europa; metabolism; methanogenesis; ocean world.

PubMed Disclaimer

Conflict of interest statement

The authors have no competing interests to declare.

Figures

Figure 1
Figure 1
Types of research discussed here for hypothesized metabolism.
See this image and copyright information in PMC

References

    1. National Academies of Sciences, Engineering, and Medicine . Origins, Worlds, Life: A Decadal Strategy for Planetary Science and Astrobiology 2023–2032. The National Academies Press; Washington, DC, USA: 2022.
    1. Hendrix A.R., Hurford T.A., Barge L.M., Bland M.T., Bowman J.S., Brinckerhoff W., Buratti B.J., Cable M.L., Castillo-Rogez J., Collins G.C., et al. The NASA Roadmap to Ocean Worlds. Astrobiology. 2008;19:1–27. doi: 10.1089/ast.2018.1955. - DOI - PMC - PubMed
    1. Pappalardo R.T., Belton M.J.S., Breneman H.H., Carr M.H., Chapman C.R., Collins G.C., Denk T., Fagents S., Geissler P.E., Giese B., et al. Does Europa have a subsurface ocean? Evaluation of the geological evidence. J. Geophys. Res. Planets. 1999;104:24015–24055. doi: 10.1029/1998JE000628. - DOI
    1. Stevenson D. Europa’s Ocean--the Case Strengthens. Science. 2000;289:1305–1307. doi: 10.1126/science.289.5483.1305. - DOI - PubMed
    1. Postberg F., Schmidt J., Hillier J., Kempf S., Srama R. A salt-water reservoir as the source of a compositionally stratified plume on Enceladus. Nature. 2011;474:620–622. doi: 10.1038/nature10175. - DOI - PubMed

LinkOut - more resources