Liquid water in comets: implications for astrobiology

J. T. Wickramasinghe; N. C. Wickramasinghe; W. M. Napier

doi:10.1117/12.768445

1 October 2007 Liquid water in comets: implications for astrobiology

J. T. Wickramasinghe, N. C. Wickramasinghe, W. M. Napier

Proceedings Volume 6694, Instruments, Methods, and Missions for Astrobiology X; 66940A (2007) https://doi.org/10.1117/12.768445
Event: Optical Engineering + Applications, 2007, San Diego, California, United States

Abstract

We show that radiogenic heating in primordial comets of radii in excess of ~10km could produce liquid water cores persisting for hundreds of thousands to millions of years. Supposing comets were seeded with even the smallest numbers of viable microbes at the time of their formation from pre-solar material, there is ample time for exponential amplification within the liquid interiors before refreezing occurs. Freeze-dried biological material is returned to interplanetary and interstellar space during cometary activity as the outer layers of comets are stripped away via sublimation. Modelling of the post-impact 8-12μm spectra of Tempel 1 gives a strong indication of mixtures of clays and organics in comparable quantity, clays in turn providing evidence of a liquid water history of the comet. The totality of comets in a galaxy or a cluster of galaxies, seems to provide a far more promising setting for an origin of life than any setting thus far proposed in relation to the primitive Earth. Once life has originated in a comet mechanisms of interstellar panspermia that have recently been identified will disperse throughout the Galaxy within a few billion years. Keywords: Comets, liquid water, clay, organics, origin of life, panspermia

Citation Download Citation

J. T. Wickramasinghe, N. C. Wickramasinghe, and W. M. Napier "Liquid water in comets: implications for astrobiology", Proc. SPIE 6694, Instruments, Methods, and Missions for Astrobiology X, 66940A (1 October 2007); https://doi.org/10.1117/12.768445

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available