Journal ArticleDOI
The organic nature of cometary grains
TLDR
In this article, a model with varying contributions from bacterial-type and viral-type particles, and with small additional contributions arising from degraded organic molecules at grain surfaces, is presented.Abstract:
Infrared observations of comets over the 2–4 Μm waveband are interpreted in terms of a model with varying contributions from bacterial-type and viral-type particles, and with small additional contributions arising from degraded organic molecules at grain surfaces.read more
Citations
More filters
Journal ArticleDOI
Influenza--evidence against contagion: discussion paper.
Fred Hoyle,N. C. Wickramasinghe +1 more
TL;DR: At the end of the last century most medical practitioners took it for granted that influenza could not be fully reconciled with the idea of contagion alone, and person-toperson spread was considered an unlikely mechanism to operate over relatively large geographical areas.
Journal ArticleDOI
Significant broadband extinction abilities of bioaerosols
TL;DR: In this article, the authors measured the reflectance spectra of 12 common biomaterials and calculated their complex refractive indexes at wavelengths of approximately 0.7, 2.1, 6.1 and 9.5μm.
Journal ArticleDOI
Cometary habitats for primitive life.
TL;DR: Subsurface lakes on the Europa model, though insulated by some metres of ice, would require a trigger (perhaps meteorite impact and energy source) to initiate and maintain a suitable-habitat on short period comets.
Book ChapterDOI
Elevating the Status of Dust
TL;DR: The subject of interstellar grains has grown enormously in stature over the past 40 years, the duration of my collaboration with Fred Hoyle as mentioned in this paper, in large measure due to Fred's prescient inputs into this subject and his encouragement.
Journal ArticleDOI
Cometary organics and the 3.4μm spectral feature
TL;DR: The 3.4μm feature corresponds to stretching vibrations of the C-H bond, with details over 3.3-3.5μm depending on neigbouring molecular bonds as mentioned in this paper.
References
More filters
Journal ArticleDOI
The organic component in dust from comet Halley as measured by the PUMA mass spectrometer on board Vega 1
Jochen Kissel,F. R. Krueger +1 more
TL;DR: In this paper, the composition of cometary dust has been analyzed by mass spectroscopy, showing that most particles consist of a predominantly chondritic core with an organic mantle composed mainly of highly unsaturated compounds.
Journal ArticleDOI
Composition of comet Halley dust particles from Giotto observations
Jochen Kissel,Donald E. Brownlee,K. Büchler,Benton C. Clark,Hugo Fechtig,Eberhard Grün,Klaus Hornung,Eduard Igenbergs,Elmar K. Jessberger,F. R. Krueger,H. Kuczera,J. A. M. McDonnell,G. M. Morfill,J. Rahe,Gerhard Schwehm,Z. Sekanina,N. G. Utterback,Heinrich J. Völk,H. A. Zook +18 more
TL;DR: The mass spectra of cometary dust particles measured by the PIA dust particle analyzer aboard the Giotto spacecraft showed some unexpected and striking features as mentioned in this paper, such as small particles below 10 to the -14th g are much more abundant than anticipated by models.
Journal ArticleDOI
Discovery of organic grains in comet Halley
D. T. Wickramasinghe,D.A. Allen +1 more
TL;DR: In this paper, a broad absorption band at a central wavelength of 3.4 μm along the line of sight to IRS7, a luminous star near the galactic centre, was detected in the spectrum of the comet Halley.
Journal ArticleDOI
Diffuse interstellar absorption bands between 2.9 and 4.0 µm
D. A. Allen,D. T. Wickramasinghe +1 more
TL;DR: In this paper, a broad absorption trough with numerous discrete features stretching from 2.9 to 3.6 µm was found, indicating that complex organic molecules may be involved in the absorption process.
Diversity and similarity of comets
TL;DR: The evolution of comets from an early stage where they were all similar, to the later diversity is reviewed in this article, where the elemental abundances of pristine comets are likely to be primitive, that is in solar abundance ratios for all elements including C, N, O, S, but with the exception of H (and assumedly He and Ne) that are severely depleted.
Related Papers (5)
Refractory and semi-volatile organics at the surface of comet 67P/Churyumov-Gerasimenko: Insights from the VIRTIS/Rosetta imaging spectrometer
Eric Quirico,L. Moroz,Bernard Schmitt,Gabriele Arnold,M. Faure,Pierre Beck,Lydie Bonal,Mauro Ciarniello,Fabrizio Capaccioni,Gianrico Filacchione,Stéphane Erard,C. Leyrat,Dominique Bockelée-Morvan,Angelo Zinzi,Ernesto Palomba,Pierre Drossart,Federico Tosi,Maria Teresa Capria,M. C. De Sanctis,Andrea Raponi,S. Fonti,F. Mancarella,Vincenzo Orofino,Antonella Barucci,M. I. Blecka,R. W. Carlson,D. Despan,Alexandre Faure,Sonia Fornasier,Murthy S. Gudipati,Andrea Longobardo,Kathrin Markus,Vito Mennella,F. Merlin,Giuseppe Piccioni,Batiste Rousseau,Fredric W. Taylor +36 more