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  1. Article: D

    Altwegg, K / Balsiger, H / Berthelier, J J / Bieler, A / Calmonte, U / De Keyser, J / Fiethe, B / Fuselier, S A / Gasc, S / Gombosi, T I / Owen, T / Le Roy, L / Rubin, M / Sémon, T / Tzou, C-Y

    Philosophical transactions. Series A, Mathematical, physical, and engineering sciences

    2017  Volume 375, Issue 2097

    Abstract: The European Rosetta mission has been following comet 67P/Churyumov-Gerasimenko for 2 years, studying the nucleus and coma in great detail. For most of these 2 years the Rosetta Orbiter Sensor for Ion and Neutral Analysis (ROSINA) has analysed the ... ...

    Abstract The European Rosetta mission has been following comet 67P/Churyumov-Gerasimenko for 2 years, studying the nucleus and coma in great detail. For most of these 2 years the Rosetta Orbiter Sensor for Ion and Neutral Analysis (ROSINA) has analysed the volatile part of the coma. With its high mass resolution and sensitivity it was able to not only detect deuterated water HDO, but also doubly deuterated water, D
    Language English
    Publishing date 2017--13
    Publishing country England
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, Non-U.S. Gov't
    ZDB-ID 208381-4
    ISSN 1471-2962 ; 1364-503X ; 0080-4614 ; 0264-3820 ; 0264-3952
    ISSN (online) 1471-2962
    ISSN 1364-503X ; 0080-4614 ; 0264-3820 ; 0264-3952
    DOI 10.1098/rsta.2016.0253
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Photochemistry of forbidden oxygen lines in the inner coma of 67P/Churyumov-Gerasimenko.

    Cessateur, G / Keyser, J De / Maggiolo, R / Gibbons, A / Gronoff, G / Gunell, H / Dhooghe, F / Loreau, J / Vaeck, N / Altwegg, K / Bieler, A / Briois, C / Calmonte, U / Combi, M R / Fiethe, B / Fuselier, S A / Gombosi, T I / Hässig, M / Le Roy, L /
    Neefs, E / Rubin, M / Sémon, T

    Journal of geophysical research. Space physics

    2016  Volume 121, Issue 1, Page(s) 804–816

    Abstract: Observations of the green and red-doublet emission lines have previously been realized for several comets. We present here a chemistry-emission coupled model to study the production and loss mechanisms of the O( ...

    Abstract Observations of the green and red-doublet emission lines have previously been realized for several comets. We present here a chemistry-emission coupled model to study the production and loss mechanisms of the O(
    Language English
    Publishing date 2016-01-28
    Publishing country United States
    Document type Journal Article
    ISSN 2169-9380
    ISSN 2169-9380
    DOI 10.1002/2015JA022013
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Xenon isotopes in 67P/Churyumov-Gerasimenko show that comets contributed to Earth's atmosphere.

    Marty, B / Altwegg, K / Balsiger, H / Bar-Nun, A / Bekaert, D V / Berthelier, J-J / Bieler, A / Briois, C / Calmonte, U / Combi, M / De Keyser, J / Fiethe, B / Fuselier, S A / Gasc, S / Gombosi, T I / Hansen, K C / Hässig, M / Jäckel, A / Kopp, E /
    Korth, A / Le Roy, L / Mall, U / Mousis, O / Owen, T / Rème, H / Rubin, M / Sémon, T / Tzou, C-Y / Waite, J H / Wurz, P

    Science (New York, N.Y.)

    2017  Volume 356, Issue 6342, Page(s) 1069–1072

    Abstract: The origin of cometary matter and the potential contribution of comets to inner-planet atmospheres are long-standing problems. During a series of dedicated low-altitude orbits, the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on the ...

    Abstract The origin of cometary matter and the potential contribution of comets to inner-planet atmospheres are long-standing problems. During a series of dedicated low-altitude orbits, the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on the Rosetta spacecraft analyzed the isotopes of xenon in the coma of comet 67P/Churyumov-Gerasimenko. The xenon isotopic composition shows deficits in heavy xenon isotopes and matches that of a primordial atmospheric component. The present-day Earth atmosphere contains 22 ± 5% cometary xenon, in addition to chondritic (or solar) xenon.
    Language English
    Publishing date 2017--09
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.aal3496
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Cometary science. 67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio.

    Altwegg, K / Balsiger, H / Bar-Nun, A / Berthelier, J J / Bieler, A / Bochsler, P / Briois, C / Calmonte, U / Combi, M / De Keyser, J / Eberhardt, P / Fiethe, B / Fuselier, S / Gasc, S / Gombosi, T I / Hansen, K C / Hässig, M / Jäckel, A / Kopp, E /
    Korth, A / LeRoy, L / Mall, U / Marty, B / Mousis, O / Neefs, E / Owen, T / Rème, H / Rubin, M / Sémon, T / Tzou, C-Y / Waite, H / Wurz, P

    Science (New York, N.Y.)

    2015  Volume 347, Issue 6220, Page(s) 1261952

    Abstract: The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to- ... ...

    Abstract The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to-hydrogen (D/H) ratios in the reservoirs for comets and Earth's oceans. Here, we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard the European Space Agency's Rosetta spacecraft, which is found to be (5.3 ± 0.7) × 10(-4)—that is, approximately three times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.
    Language English
    Publishing date 2015-01-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.1261952
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Cometary science. Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko.

    Hässig, M / Altwegg, K / Balsiger, H / Bar-Nun, A / Berthelier, J J / Bieler, A / Bochsler, P / Briois, C / Calmonte, U / Combi, M / De Keyser, J / Eberhardt, P / Fiethe, B / Fuselier, S A / Galand, M / Gasc, S / Gombosi, T I / Hansen, K C / Jäckel, A /
    Keller, H U / Kopp, E / Korth, A / Kührt, E / Le Roy, L / Mall, U / Marty, B / Mousis, O / Neefs, E / Owen, T / Rème, H / Rubin, M / Sémon, T / Tornow, C / Tzou, C-Y / Waite, J H / Wurz, P

    Science (New York, N.Y.)

    2015  Volume 347, Issue 6220, Page(s) aaa0276

    Abstract: Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and chemical conditions during the early solar system when comets formed. ROSINA (Rosetta Orbiter ... ...

    Abstract Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and chemical conditions during the early solar system when comets formed. ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) onboard the Rosetta spacecraft has measured the coma composition of comet 67P/Churyumov-Gerasimenko with well-sampled time resolution per rotation. Measurements were made over many comet rotation periods and a wide range of latitudes. These measurements show large fluctuations in composition in a heterogeneous coma that has diurnal and possibly seasonal variations in the major outgassing species: water, carbon monoxide, and carbon dioxide. These results indicate a complex coma-nucleus relationship where seasonal variations may be driven by temperature differences just below the comet surface.
    Language English
    Publishing date 2015-01-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.aaa0276
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Molecular nitrogen in comet 67P/Churyumov-Gerasimenko indicates a low formation temperature.

    Rubin, M / Altwegg, K / Balsiger, H / Bar-Nun, A / Berthelier, J-J / Bieler, A / Bochsler, P / Briois, C / Calmonte, U / Combi, M / De Keyser, J / Dhooghe, F / Eberhardt, P / Fiethe, B / Fuselier, S A / Gasc, S / Gombosi, T I / Hansen, K C / Hässig, M /
    Jäckel, A / Kopp, E / Korth, A / Le Roy, L / Mall, U / Marty, B / Mousis, O / Owen, T / Rème, H / Sémon, T / Tzou, C-Y / Waite, J H / Wurz, P

    Science (New York, N.Y.)

    2015  Volume 348, Issue 6231, Page(s) 232–235

    Abstract: Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets ... ...

    Abstract Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets formed. Yet in comets, often considered the most primitive bodies in the solar system, N2 has not been detected. Here we report the direct in situ measurement of N2 in the Jupiter family comet 67P/Churyumov-Gerasimenko, made by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer aboard the Rosetta spacecraft. A N2/CO ratio of (5.70 ± 0.66) × 10(-3) (2σ standard deviation of the sampled mean) corresponds to depletion by a factor of ~25.4 ± 8.9 as compared to the protosolar value. This depletion suggests that cometary grains formed at low-temperature conditions below ~30 kelvin.
    Language English
    Publishing date 2015-04-10
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.aaa6100
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Abundant molecular oxygen in the coma of comet 67P/Churyumov-Gerasimenko.

    Bieler, A / Altwegg, K / Balsiger, H / Bar-Nun, A / Berthelier, J-J / Bochsler, P / Briois, C / Calmonte, U / Combi, M / De Keyser, J / van Dishoeck, E F / Fiethe, B / Fuselier, S A / Gasc, S / Gombosi, T I / Hansen, K C / Hässig, M / Jäckel, A / Kopp, E /
    Korth, A / Le Roy, L / Mall, U / Maggiolo, R / Marty, B / Mousis, O / Owen, T / Rème, H / Rubin, M / Sémon, T / Tzou, C-Y / Waite, J H / Walsh, C / Wurz, P

    Nature

    2015  Volume 526, Issue 7575, Page(s) 678–681

    Abstract: The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density. In addition, cometary comas have been found to contain a rich array of other molecules, ... ...

    Abstract The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density. In addition, cometary comas have been found to contain a rich array of other molecules, including sulfuric compounds and complex hydrocarbons. Molecular oxygen (O2), however, despite its detection on other icy bodies such as the moons of Jupiter and Saturn, has remained undetected in cometary comas. Here we report in situ measurement of O2 in the coma of comet 67P/Churyumov-Gerasimenko, with local abundances ranging from one per cent to ten per cent relative to H2O and with a mean value of 3.80 ± 0.85 per cent. Our observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance. This suggests that primordial O2 was incorporated into the nucleus during the comet's formation, which is unexpected given the low upper limits from remote sensing observations. Current Solar System formation models do not predict conditions that would allow this to occur.
    MeSH term(s) Carbon Monoxide/analysis ; Extraterrestrial Environment/chemistry ; Ice/analysis ; Meteoroids ; Nitrogen/analysis ; Oxygen/analysis ; Oxygen/radiation effects ; Photolysis ; Solar System/chemistry ; Spacecraft ; Water/analysis
    Chemical Substances Ice ; Water (059QF0KO0R) ; Carbon Monoxide (7U1EE4V452) ; Nitrogen (N762921K75) ; Oxygen (S88TT14065)
    Language English
    Publishing date 2015-10-29
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/nature15707
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  8. Article ; Online: Krypton isotopes and noble gas abundances in the coma of comet 67P/Churyumov-Gerasimenko.

    Rubin, Martin / Altwegg, Kathrin / Balsiger, Hans / Bar-Nun, Akiva / Berthelier, Jean-Jacques / Briois, Christelle / Calmonte, Ursina / Combi, Michael / De Keyser, Johan / Fiethe, Björn / Fuselier, Stephen A / Gasc, Sebastien / Gombosi, Tamas I / Hansen, Kenneth C / Kopp, Ernest / Korth, Axel / Laufer, Diana / Le Roy, Léna / Mall, Urs /
    Marty, Bernard / Mousis, Olivier / Owen, Tobias / Rème, Henri / Sémon, Thierry / Tzou, Chia-Yu / Waite, Jack H / Wurz, Peter

    Science advances

    2018  Volume 4, Issue 7, Page(s) eaar6297

    Abstract: The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer Double Focusing Mass Spectrometer on board the European Space Agency's Rosetta spacecraft detected the major isotopes of the noble gases argon, krypton, and xenon in the coma ...

    Abstract The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer Double Focusing Mass Spectrometer on board the European Space Agency's Rosetta spacecraft detected the major isotopes of the noble gases argon, krypton, and xenon in the coma of comet 67P/Churyumov-Gerasimenko. Earlier, it was found that xenon exhibits an isotopic composition distinct from anywhere else in the solar system. However, argon isotopes, within error, were shown to be consistent with solar isotope abundances. This discrepancy suggested an additional exotic component of xenon in comet 67P/Churyumov-Gerasimenko. We show that krypton also exhibits an isotopic composition close to solar. Furthermore, we found the argon to krypton and the krypton to xenon ratios in the comet to be lower than solar, which is a necessity to postulate an addition of exotic xenon in the comet.
    Language English
    Publishing date 2018-07-04
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, Non-U.S. Gov't
    ZDB-ID 2810933-8
    ISSN 2375-2548 ; 2375-2548
    ISSN (online) 2375-2548
    ISSN 2375-2548
    DOI 10.1126/sciadv.aar6297
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Prebiotic chemicals-amino acid and phosphorus-in the coma of comet 67P/Churyumov-Gerasimenko.

    Altwegg, Kathrin / Balsiger, Hans / Bar-Nun, Akiva / Berthelier, Jean-Jacques / Bieler, Andre / Bochsler, Peter / Briois, Christelle / Calmonte, Ursina / Combi, Michael R / Cottin, Hervé / De Keyser, Johan / Dhooghe, Frederik / Fiethe, Bjorn / Fuselier, Stephen A / Gasc, Sébastien / Gombosi, Tamas I / Hansen, Kenneth C / Haessig, Myrtha / Jäckel, Annette /
    Kopp, Ernest / Korth, Axel / Le Roy, Lena / Mall, Urs / Marty, Bernard / Mousis, Olivier / Owen, Tobias / Rème, Henri / Rubin, Martin / Sémon, Thierry / Tzou, Chia-Yu / Hunter Waite, James / Wurz, Peter

    Science advances

    2016  Volume 2, Issue 5, Page(s) e1600285

    Abstract: The importance of comets for the origin of life on Earth has been advocated for many decades. Amino acids are key ingredients in chemistry, leading to life as we know it. Many primitive meteorites contain amino acids, and it is generally believed that ... ...

    Abstract The importance of comets for the origin of life on Earth has been advocated for many decades. Amino acids are key ingredients in chemistry, leading to life as we know it. Many primitive meteorites contain amino acids, and it is generally believed that these are formed by aqueous alterations. In the collector aerogel and foil samples of the Stardust mission after the flyby at comet Wild 2, the simplest form of amino acids, glycine, has been found together with precursor molecules methylamine and ethylamine. Because of contamination issues of the samples, a cometary origin was deduced from the (13)C isotopic signature. We report the presence of volatile glycine accompanied by methylamine and ethylamine in the coma of 67P/Churyumov-Gerasimenko measured by the ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) mass spectrometer, confirming the Stardust results. Together with the detection of phosphorus and a multitude of organic molecules, this result demonstrates that comets could have played a crucial role in the emergence of life on Earth.
    MeSH term(s) Amino Acids/chemistry ; Mass Spectrometry/methods ; Meteoroids ; Phosphorus/chemistry ; Prebiotics/analysis
    Chemical Substances Amino Acids ; Prebiotics ; Phosphorus (27YLU75U4W)
    Language English
    Publishing date 2016-05-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2810933-8
    ISSN 2375-2548 ; 2375-2548
    ISSN (online) 2375-2548
    ISSN 2375-2548
    DOI 10.1126/sciadv.1600285
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Detection of argon in the coma of comet 67P/Churyumov-Gerasimenko.

    Balsiger, Hans / Altwegg, Kathrin / Bar-Nun, Akiva / Berthelier, Jean-Jacques / Bieler, Andre / Bochsler, Peter / Briois, Christelle / Calmonte, Ursina / Combi, Michael / De Keyser, Johan / Eberhardt, Peter / Fiethe, Björn / Fuselier, Stephen A / Gasc, Sébastien / Gombosi, Tamas I / Hansen, Kenneth C / Hässig, Myrtha / Jäckel, Annette / Kopp, Ernest /
    Korth, Axel / Le Roy, Lena / Mall, Urs / Marty, Bernard / Mousis, Olivier / Owen, Tobias / Rème, Henri / Rubin, Martin / Sémon, Thierry / Tzou, Chia-Yu / Waite, J Hunter / Wurz, Peter

    Science advances

    2015  Volume 1, Issue 8, Page(s) e1500377

    Abstract: Comets have been considered to be representative of icy planetesimals that may have contributed a significant fraction of the volatile inventory of the terrestrial planets. For example, comets must have brought some water to Earth. However, the magnitude ...

    Abstract Comets have been considered to be representative of icy planetesimals that may have contributed a significant fraction of the volatile inventory of the terrestrial planets. For example, comets must have brought some water to Earth. However, the magnitude of their contribution is still debated. We report the detection of argon and its relation to the water abundance in the Jupiter family comet 67P/Churyumov-Gerasimenko by in situ measurement of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) mass spectrometer aboard the Rosetta spacecraft. Despite the very low intensity of the signal, argon is clearly identified by the exact determination of the mass of the isotope (36)Ar and by the (36)Ar/(38)Ar ratio. Because of time variability and spatial heterogeneity of the coma, only a range of the relative abundance of argon to water can be given. Nevertheless, this range confirms that comets of the type 67P/Churyumov-Gerasimenko cannot be the major source of Earth's major volatiles.
    Language English
    Publishing date 2015-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2810933-8
    ISSN 2375-2548
    ISSN 2375-2548
    DOI 10.1126/sciadv.1500377
    Database MEDical Literature Analysis and Retrieval System OnLINE

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