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• Goetz, Charlotte; Herbert, Gunell; Volwerk, Martin; A., Beth; Eriksson, A. & Galand, M [Vis alle 30 forfattere av denne artikkelen] (2021). Cometary plasma science: Open science questions for future space missions. Experimental astronomy (Print). ISSN 0922-6435. doi: 10.1007/s10686-021-09783-z. Fulltekst i vitenarkiv Vis sammendrag

  Comets hold the key to the understanding of our Solar System, its formation and its evolution, and to the fundamental plasma processes at work both in it and beyond it. A comet nucleus emits gas as it is heated by the sunlight. The gas forms the coma, where it is ionised, becomes a plasma, and eventually interacts with the solar wind. Besides these neutral and ionised gases, the coma also contains dust grains, released from the comet nucleus. As a cometary atmosphere develops when the comet travels through the Solar System, large-scale structures, such as the plasma boundaries, develop and disappear, while at planets such large-scale structures are only accessible in their fully grown, quasi-steady state. In situ measurements at comets enable us to learn both how such large-scale structures are formed or reformed and how small-scale processes in the plasma affect the formation and properties of these large scale structures. Furthermore, a comet goes through a wide range of parameter regimes during its life cycle, where either collisional processes, involving neutrals and charged particles, or collisionless processes are at play, and might even compete in complicated transitional regimes. Thus a comet presents a unique opportunity to study this parameter space, from an asteroid-like to a Mars- and Venus-like interaction. The Rosetta mission and previous fast flybys of comets have together made many new discoveries, but the most important breakthroughs in the understanding of cometary plasmas are yet to come. The Comet Interceptor mission will provide a sample of multi-point measurements at a comet, setting the stage for a multi-spacecraft mission to accompany a comet on its journey through the Solar System. This White Paper, submitted in response to the European Space Agency’s Voyage 2050 call, reviews the present-day knowledge of cometary plasmas, discusses the many questions that remain unanswered, and outlines a multi-spacecraft European Space Agency mission to accompany a comet that will answer these questions by combining both multi-spacecraft observations and a rendezvous mission, and at the same time advance our understanding of fundamental plasma physics and its role in planetary systems.

• Alho, Markku; Wedlund, Cyril Simon; Nilsson, Hans; Kallio, Esa; Jarvinen, R & Pulkkinen, T.I. (2019). Hybrid modeling of cometary plasma environments - II. Remote-sensing of a cometary bow shock. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 630. doi: 10.1051/0004-6361/201834863. Fulltekst i vitenarkiv Vis sammendrag

  Context. The ESA Rosetta probe has not seen direct evidence of a fully formed bow shock at comet 67P/Churyumov–Gerasimenko (67P). Ion spectrometer measurements of cometary pickup ions measured in the vicinity of the nucleus of 67P are available and may contain signatures of the large-scale plasma environment. Aims. The aim is to investigate the possibility of using pickup ion signatures to infer the existence or nonexistence of a bow shock-like structure and possibly other large-scale plasma environment features. Methods. A numerical plasma model in the hybrid plasma description was used to model the plasma environment of a comet. Simulated pickup ion spectra were generated for different interplanetary magnetic field conditions. The results were interpreted through test particle tracing in the hybrid simulation solutions. Results. Features of the observed pickup ion energy spectrum were reproduced, and the model was used to interpret the observation to be consistent with a shock-like structure. We identify (1) a spectral break related to the bow shock, (2) a mechanism for generating the spectral break, and (3) a dependency of the energy of the spectral break on the interplanetary magnetic field magnitude and bow shock standoff distance.

• Wedlund, Cyril Simon; Behar, Etienne; Nilsson, Hans; Alho, Markku; Kallio, Esa & Gunell, Herbert [Vis alle 14 forfattere av denne artikkelen] (2019). Solar wind charge exchange in cometary atmospheres - III. Results from the Rosetta mission to comet 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 630. doi: 10.1051/0004-6361/201834881. Fulltekst i vitenarkiv Vis sammendrag

  Context. Solar wind charge-changing reactions are of paramount importance to the physico-chemistry of the atmosphere of a comet. The ESA/Rosetta mission to comet 67P/Churyumov-Gerasimenko (67P) provides a unique opportunity to study charge-changing processes in situ. Aims. To understand the role of these reactions in the evolution of the solar wind plasma and interpret the complex in situ measurements made by Rosetta, numerical or analytical models are necessary. Methods. We used an extended analytical formalism describing solar wind charge-changing processes at comets along solar wind streamlines. The model is driven by solar wind ion measurements from the Rosetta Plasma Consortium-Ion Composition Analyser (RPC-ICA) and neutral density observations from the Rosetta Spectrometer for Ion and Neutral Analysis-Comet Pressure Sensor (ROSINA-COPS), as well as by charge-changing cross sections of hydrogen and helium particles in a water gas. Results. A mission-wide overview of charge-changing efficiencies at comet 67P is presented. Electron capture cross sections dominate and favor the production of He and H energetic neutral atoms (ENAs), with fluxes expected to rival those of H+ and He2+ ions. Conclusions. Neutral outgassing rates are retrieved from local RPC-ICA flux measurements and match ROSINA estimates very well throughout the mission. From the model, we find that solar wind charge exchange is unable to fully explain the magnitude of the sharp drop in solar wind ion fluxes observed by Rosetta for heliocentric distances below 2.5 AU. This is likely because the model does not take the relative ion dynamics into account and to a lesser extent because it ignores the formation of bow-shock-like structures upstream of the nucleus. This work also shows that the ionization by solar extreme-ultraviolet radiation and energetic electrons dominates the source of cometary ions, although solar wind contributions may be significant during isolated events.

• Edberg, Niklas J.T.; Johansson, F. L.; Eriksson, Anders I.; Andrews, D. J.; Hajra, Rajkumar & Henri, Pierre [Vis alle 9 forfattere av denne artikkelen] (2019). Solar flares observed by Rosetta at comet 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 630. doi: 10.1051/0004-6361/201834834. Fulltekst i vitenarkiv Vis sammendrag

  Context. The Rosetta spacecraft made continuous measurements of the coma of comet 67P/Churyumov-Gerasimenko (67P) for more than two years. The plasma in the coma appeared very dynamic, and many factors control its variability. Aims. We wish to identify the effects of solar flares on the comet plasma and also their effect on the measurements by the Langmuir Probe Instrument (LAP). Methods. To identify the effects of flares, we proceeded from an existing flare catalog of Earth-directed solar flares, from which a new list was created that only included Rosetta-directed flares. We also used measurements of flares at Mars when at similar longitudes as Rosetta. The flare irradiance spectral model (FISM v.1) and its Mars equivalent (FISM-M) produce an extreme-ultraviolet (EUV) irradiance (10–120 nm) of the flares at 1 min resolution. LAP data and density measurements obtained with the Mutual Impedence Probe (MIP) from the time of arrival of the flares at Rosetta were examined to determine the flare effects. Results. From the vantage point of Earth, 1504 flares directed toward Rosetta occurred during the mission. In only 24 of these, that is, 1.6%, was the increase in EUV irradiance large enough to cause an observable effect in LAP data. Twenty-four Mars-directed flares were also observed in Rosetta data. The effect of the flares was to increase the photoelectron current by typically 1–5 nA. We find little evidence that the solar flares increase the plasma density, at least not above the background variability. Conclusions. Solar flares have a small effect on the photoelectron current of the LAP instrument, and they are not significant in comparison to other factors that control the plasma density in the coma. The photoelectron current can only be used for flare detection during periods of calm plasma conditions.

• Wedlund, Cyril Simon; Behar, Etienne; Kallio, Esa; Nilsson, Hans; Alho, Markku & Gunell, Herbert [Vis alle 10 forfattere av denne artikkelen] (2019). Solar wind charge exchange in cometary atmospheres - II. Analytical model. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 630. doi: 10.1051/0004-6361/201834874. Fulltekst i vitenarkiv Vis sammendrag

  Context. Solar wind charge-changing reactions are of paramount importance to the physico-chemistry of the atmosphere of a comet because they mass-load the solar wind through an effective conversion of fast, light solar wind ions into slow, heavy cometary ions. The ESA/Rosetta mission to comet 67P/Churyumov-Gerasimenko (67P) provided a unique opportunity to study charge-changing processes in situ. Aims. To understand the role of charge-changing reactions in the evolution of the solar wind plasma and to interpret the complex in situ measurements made by Rosetta, numerical or analytical models are necessary. Methods. An extended analytical formalism describing solar wind charge-changing processes at comets along solar wind streamlines is presented. It is based on a thorough book-keeping of available charge-changing cross sections of hydrogen and helium particles in a water gas. Results. After presenting a general 1D solution of charge exchange at comets, we study the theoretical dependence of charge-state distributions of (He2+, He+, He0) and (H+, H0, H−) on solar wind parameters at comet 67P. We show that double charge exchange for the He2+−H2O system plays an important role below a solar wind bulk speed of 200 km s−1, resulting in the production of He energetic neutral atoms, whereas stripping reactions can in general be neglected. Retrievals of outgassing rates and solar wind upstream fluxes from local Rosetta measurements deep in the coma are discussed. Solar wind ion temperature effects at 400 km s−1 solar wind speed are well contained during the Rosetta mission. Conclusions. As the comet approaches perihelion, the model predicts a sharp decrease of solar wind ion fluxes by almost one order of magnitude at the location of Rosetta, forming in effect a solar wind ion cavity. This study is the second part of a series of three on solar wind charge-exchange and ionization processes at comets, with a specific application to comet 67P and the Rosetta mission.

• Wedlund, Cyril Simon; Bodewits, Dennis; Alho, Markku; Hoekstra, Ronnie; Behar, Etienne & Gronoff, Guillaume [Vis alle 10 forfattere av denne artikkelen] (2019). Solar wind charge exchange in cometary atmospheres - I. Charge-changing and ionization cross sections for He and H particles in H2O. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 630, s. 1–22. doi: 10.1051/0004-6361/201834848. Fulltekst i vitenarkiv Vis sammendrag

  Context. Solar wind charge-changing reactions are of paramount importance to the physico-chemistry of the atmosphere of a comet, mass-loading the solar wind through an effective conversion of fast light solar wind ions into slow heavy cometary ions. Aims. To understand these processes and place them in the context of a solar wind plasma interacting with a neutral atmosphere, numerical or analytical models are necessary. Inputs of these models, such as collision cross sections and chemistry, are crucial. Methods. Book-keeping and fitting of experimentally measured charge-changing and ionization cross sections of hydrogen and helium particles in a water gas are discussed, with emphasis on the low-energy/low-velocity range that is characteristic of solar wind bulk speeds (<20 keV u−1/2000 km s−1). Results. We provide polynomial fits for cross sections of charge-changing and ionization reactions, and list the experimental needs for future studies. To take into account the energy distribution of the solar wind, we calculated Maxwellian-averaged cross sections and fitted them with bivariate polynomials for solar wind temperatures ranging from 105 to 106 K (12–130 eV). Conclusions. Single- and double-electron captures by He2+ dominate at typical solar wind speeds. Correspondingly, single-electron capture by H+ and single-electron loss by H− dominate at these speeds, resulting in the production of energetic neutral atoms (ENAs). Ionization cross sections all peak at energies above 20 keV and are expected to play a moderate role in the total ion production. However, the effect of solar wind Maxwellian temperatures is found to be maximum for cross sections peaking at higher energies, suggesting that local heating at shock structures in cometary and planetary environments may favor processes previously thought to be negligible. This study is the first part in a series of three on charge exchange and ionization processes at comets, with a specific application to comet 67P/Churyumov-Gerasimenko and the Rosetta mission.

• Madsen, Birgitte; Wedlund, Cyril Simon; Eriksson, A.; Goetz, C.; Karlsson, T. & Gunell, H. [Vis alle 10 forfattere av denne artikkelen] (2018). Extremely Low-Frequency Waves Inside the Diamagnetic Cavity of Comet 67P/Churyumov-Gerasimenko. Geophysical Research Letters. ISSN 0094-8276. 45(9), s. 3854–3864. doi: 10.1029/2017GL076415. Fulltekst i vitenarkiv Vis sammendrag

  The European Space Agency/Rosetta mission to comet 67P/Churyumov-Gerasimenko has provided several hundred observations of the cometary diamagnetic cavity induced by the interaction between outgassed cometary particles, cometary ions, and the solar wind magnetic field. Here we present the first electric field measurements of four preperihelion and postperihelion cavity crossings on 28 May 2015 and 17 February 2016, using the dual-probe electric field mode of the Langmuir probe (LAP) instrument of the Rosetta Plasma Consortium. We find that on large scales, variations in the electric field fluctuations capture the cavity and boundary regions observed in the already well-studied magnetic field, suggesting the electric field mode of the LAP instrument as a reliable tool to image cavity crossings. In addition, the LAP electric field mode unravels for the first time extremely low-frequency waves within two cavities. These low-frequency electrostatic waves are likely triggered by lower-hybrid waves observed in the surrounding magnetized plasma.

• Egeland, Alv & Wedlund, Cyril Simon (2018). Birkeland's Electromagnetic Cannon. IEEE Transactions on Plasma Science. ISSN 0093-3813. 46(6), s. 2154–2161. doi: 10.1109/TPS.2018.2834980. Fulltekst i vitenarkiv
• Noonan, John W.; Stern, S. Alan; Feldman, Paul D.; Broiles, Thomas; Wedlund, Cyril Simon & Edberg, Niklas J.T. [Vis alle 16 forfattere av denne artikkelen] (2018). Ultraviolet observations of coronal mass ejection impact on comet 67P/Churyumov-Gerasimenko by Rosetta Alice. Astronomical Journal. ISSN 0004-6256. 156:16, s. 1–11. doi: 10.3847/1538-3881/aac432. Fulltekst i vitenarkiv Vis sammendrag

  The Alice ultraviolet spectrograph on the European Space Agency Rosetta spacecraft observed comet 67P/Churyumov–Gerasimenko in its orbit around the Sun for just over two years. Alice observations taken in 2015 October, two months after perihelion, show large increases in the comet's Lyβ, O i 1304, O i 1356, and C i 1657 Å atomic emission that initially appeared to indicate gaseous outbursts. However, the Rosetta Plasma Consortium instruments showed a coronal mass ejection (CME) impact at the comet coincident with the emission increases, suggesting that the CME impact may have been the cause of the increased emission. The presence of the semi-forbidden O i 1356 Å emission multiplet is indicative of a substantial increase in dissociative electron impact emission from the coma, suggesting a change in the electron population during the CME impact. The increase in dissociative electron impact could be a result of the interaction between the CME and the coma of 67P or an outburst coincident with the arrival of the CME. The observed dissociative electron impact emission during this period is used to characterize the O2 content of the coma at two peaks during the CME arrival. The mechanism that could cause the relationship between the CME and UV emission brightness is not well constrained, but we present several hypotheses to explain the correlation.

• Hajra, Rajkumar; Henri, Pierre; Myllys, Minna; Héritier, Kevin L.; Galand, Marina & Wedlund, Cyril Simon [Vis alle 17 forfattere av denne artikkelen] (2018). Cometary plasma response to interplanetary corotating interaction regions during 2016 June-September: A quantitative study by the Rosetta Plasma Consortium. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 480(4), s. 4544–4556. doi: 10.1093/mnras/sty2166. Fulltekst i vitenarkiv Vis sammendrag

  Four interplanetary corotating interaction regions (CIRs) were identified during 2016 June–September by the Rosetta Plasma Consortium (RPC) monitoring in situ the plasma environment of the comet 67P/Churyumov–Gerasimenko (67P) at heliocentric distances of ∼3–3.8 au. The CIRs, formed in the interface region between low- and high-speed solar wind streams with speeds of ∼320–400 km s−1 and ∼580–640 km s−1, respectively, are characterized by relative increases in solar wind proton density by factors of ∼13–29, in proton temperature by ∼7–29, and in magnetic field by ∼1–4 with respect to the pre-CIR values. The CIR boundaries are well defined with interplanetary discontinuities. Out of 10 discontinuities, four are determined to be forward waves and five are reverse waves, propagating at ∼5–92 per cent of the magnetosonic speed at angles of ∼20°–87° relative to ambient magnetic field. Only one is identified to be a quasi-parallel forward shock with magnetosonic Mach number of ∼1.48 and shock normal angle of ∼41°. The cometary ionosphere response was monitored by Rosetta from cometocentric distances of ∼4–30 km. A quiet time plasma density map was developed by considering dependences on cometary latitude, longitude, and cometocentric distance of Rosetta observations before and after each of the CIR intervals. The CIRs lead to plasma density enhancements of ∼500–1000 per cent with respect to the quiet time reference level. Ionospheric modelling shows that increased ionization rate due to enhanced ionizing (>12–200 eV) electron impact is the prime cause of the large cometary plasma density enhancements during the CIRs. Plausible origin mechanisms of the cometary ionizing electron enhancements are discussed.

• Gunell, Herbert; Goetz, Charlotte; Wedlund, Cyril Simon; Lindkvist, Jesper; Hamrin, Maria & Nilsson, Hans [Vis alle 9 forfattere av denne artikkelen] (2018). The infant bow shock: A new frontier at a weak activity comet. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 619, s. 1–5. doi: 10.1051/0004-6361/201834225. Fulltekst i vitenarkiv Vis sammendrag

  The bow shock is the first boundary the solar wind encounters as it approaches planets or comets. The Rosetta spacecraft was able to observe the formation of a bow shock by following comet 67P/Churyumov–Gerasimenko toward the Sun, through perihelion, and back outward again. The spacecraft crossed the newly formed bow shock several times during two periods a few months before and after perihelion; it observed an increase in magnetic field magnitude and oscillation amplitude, electron and proton heating at the shock, and the diminution of the solar wind further downstream. Rosetta observed a cometary bow shock in its infancy, a stage in its development not previously accessible to in situ measurements at comets and planets.

• Lindkvist, Jesper; Hamrin, Maria; Gunell, Herbert; Nilsson, Hans; Wedlund, Cyril Simon & Kallio, Esa [Vis alle 9 forfattere av denne artikkelen] (2018). Energy conversion in cometary atmospheres - Hybrid modeling of 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 616, s. 1–10. doi: 10.1051/0004-6361/201732353. Fulltekst i vitenarkiv Vis sammendrag

  <i>Aims</i>: We wish to investigate the energy conversion between particles and electromagnetic fields and determine the location where it occurs in the plasma environment of comets.<p> <p><i>Methods</i>: We used a hybrid plasma model that included photoionization, and we considered two cases of the solar extreme ultraviolet flux. Other parameters corresponded to the conditions of comet 67P/Churyumov–Gerasimenko at a heliocentric distance of 1.5 AU.<p> <p><i>Results</i>: We find that a shock-like structure is formed upstream of the comet and acts as an electromagnetic generator, similar to the bow shock at Earth that slows down the solar wind. The Poynting flux transports electromagnetic energy toward the inner coma, where newly born cometary ions are accelerated. Upstream of the shock-like structure, we find local energy transfer from solar wind ions to cometary ions. We show that mass loading can be a local process with a direct transfer of energy, but also part of a dynamo system with electromagnetic generators and loads.<p> <p><i>Conclusions</i>. The energization of cometary ions is governed by a dynamo system for weak ionization, but changes into a large conversion region with local transfer of energy directly from solar wind protons for high ionization.<p>

• Wieser, Gabriella Stenberg; Odelstad, Elias; Wieser, Martin; Nilsson, Hans; Goetz, C. & Karlsson, Tomas [Vis alle 13 forfattere av denne artikkelen] (2017). Investigating short-time-scale variations in cometary ions around comet 67P. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 469, s. S522–S534. doi: 10.1093/mnras/stx2133. Fulltekst i vitenarkiv
• Wedlund, Cyril Simon; Alho, M.; Gronoff, G.; Kallio, E.; Gunell, H. & Nilsson, H. [Vis alle 10 forfattere av denne artikkelen] (2017). Hybrid modelling of cometary plasma environments: I. Impact of photoionisation, charge exchange, and electron ionisation on bow shock and cometopause at 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 604. doi: 10.1051/0004-6361/201730514. Fulltekst i vitenarkiv
• Bougher, Stephen W.; Brain, David A.; Fox, Jane L.; Gonzalez-Galindo, Francisco; Wedlund, Cyril Simon & Withers, Paul G. (2017). Upper Neutral Atmosphere and Ionosphere. I Zurek, Richard W. (Red.), The Atmosphere and Climate of Mars. Cambridge University Press. ISSN 9781107016187. s. 433–463. doi: 10.1017/9781139060172.014. Fulltekst i vitenarkiv
• Johansson, Fredrik; Odelstad, E; Paulsson, Joakim John Paul; Harang, Sigve Smedsrud; Eriksson, AI & Mannel, Thurid [Vis alle 13 forfattere av denne artikkelen] (2017). Rosetta photoelectron emission and solar ultraviolet flux at comet 67P. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 469, s. S626–S635. doi: 10.1093/mnras/stx2369. Fulltekst i vitenarkiv
• Nilsson, Hans; Wieser, Gabriella Stenberg; Behar, Etienne; Gunell, Herbert; Wieser, Martin & Galand, M [Vis alle 13 forfattere av denne artikkelen] (2017). Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 469, s. S252–S261. doi: 10.1093/mnras/stx1491. Fulltekst i vitenarkiv
• Gunell, H.; Goetz, C.; Eriksson, A; Nilsson, H; Wedlund, Cyril Simon & Henri, P [Vis alle 14 forfattere av denne artikkelen] (2017). Plasma waves confined to the diamagnetic cavity of comet 67P/Churyumov–Gerasimenko. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 469, s. S84–S92. doi: 10.1093/mnras/stx1134. Fulltekst i vitenarkiv
• Gunell, H.; Nilsson, H; Hamrin, M; Eriksson, A; Odelstad, E & Maggiolo, R. [Vis alle 18 forfattere av denne artikkelen] (2017). Ion acoustic waves at comet 67P/Churyumov-Gerasimenko: Observations and computations. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 600. doi: 10.1051/0004-6361/201629801. Fulltekst i vitenarkiv
• Eriksson, AI; Engelhardt, IAD; Andre, M; Boström, R; Edberg, NJT & Johansson, F. L. [Vis alle 23 forfattere av denne artikkelen] (2017). Cold and warm electrons at comet 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 605. doi: 10.1051/0004-6361/201630159. Fulltekst i vitenarkiv
• Yang, Lei; Paulsson, Joakim John Paul; Wedlund, Cyril Simon; Odelstad, Elias; Edberg, Niklas & Koenders, C. [Vis alle 8 forfattere av denne artikkelen] (2016). Observations of high-plasma density region in the inner coma of 67P/Churyumov–Gerasimenko during early activity. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 462, s. S33–S44. doi: 10.1093/mnras/stw2046. Fulltekst i vitenarkiv
• Wedlund, Cyril Simon; Kallio, E.; Alho, M.; Nilsson, H.; Wieser, G. Stenberg & Gunell, H. [Vis alle 9 forfattere av denne artikkelen] (2016). The atmosphere of comet 67P/Churyumov-Gerasimenko diagnosed by charge-exchanged solar wind alpha particles. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 587. doi: 10.1051/0004-6361/201527532. Fulltekst i vitenarkiv
• Hansen, K. C.; Altwegg, K; Barthelier, J. -J; Bieler, Andreas; Biver, N & Bockelee-Morvan, D [Vis alle 26 forfattere av denne artikkelen] (2016). Evolution of water production of 67P/Churyumov-Gerasimenko: An empirical model and a multi-instrument study. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. s. S491–S506. doi: 10.1093/mnras/stw2413. Fulltekst i vitenarkiv
• Mandt, K.; Eriksson, A.; Edberg, Niklas; Koenders, C; Broiles, T. & Fuselier, S. [Vis alle 35 forfattere av denne artikkelen] (2016). RPC observation of the development and evolution of plasma interaction boundaries at 67P/Churyumov-Gerasimenko. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 462, s. S9–S22. doi: 10.1093/mnras/stw1736. Fulltekst i vitenarkiv
• Edberg, Niklas; Alho, M.; André, M.; Andrews, D. J.; Behar, E. & Burch, J. L. [Vis alle 26 forfattere av denne artikkelen] (2016). CME impact on comet 67P/Churyumov-Gerasimenko. Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 462, s. S45–S56. doi: 10.1093/mnras/stw2112. Fulltekst i vitenarkiv
• Gunell, Herbert; Mann, Ingrid; Wedlund, Cyril Simon; Kallio, Esa; Alho, Markku & Nilsson, Hans [Vis alle 9 forfattere av denne artikkelen] (2015). Acceleration of ions and nano dust at a comet in the solar wind. Planetary and Space Science. ISSN 0032-0633. 119, s. 13–23. Fulltekst i vitenarkiv
• Lilensten, Jean; Provan, Gabrielle; Grimald, Sandrine; Brekke, Asgeir; Flückiger, Erwin & Vanlommel, Petra [Vis alle 9 forfattere av denne artikkelen] (2013). The Planeterrella experiment: From individual initiative to networking. Journal of Space Weather and Space Climate. 3. doi: 10.1051/swsc/2013029. Fulltekst i vitenarkiv

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• Wedlund, Cyril Simon; Behar, Etienne; Nilsson, Hans; Alho, Markku; Kallio, Esa & Gunell, Herbert [Vis alle 15 forfattere av denne artikkelen] (2020). Erratum: Solar wind charge exchange in cometary atmospheres: III. Results from the Rosetta mission to comet 67P/Churyumov-Gerasimenko (Astronomy and Astrophysics (2019) 630 (A37) DOI: 10.1051/0004-6361/201834881). Astronomy and Astrophysics (A & A). ISSN 0004-6361. 640. doi: 10.1051/0004-6361/201834881e. Fulltekst i vitenarkiv
• Héritier, Kevin L.; Altwegg, Kathrin; Berthelier, Jean-Jacques; Beth, Arnaud; Carr, Cristopher M. & Keyser, Johan De [Vis alle 17 forfattere av denne artikkelen] (2018). On the origin of molecular oxygen in cometary comae. Nature Communications. 9:2580(1), s. 1–4. doi: 10.1038/s41467-018-04972-5. Fulltekst i vitenarkiv
• Nilsson, Hans; Wieser, Gabriella Stenberg; Behar, Etienne; Gunell, Herbert; Wieser, Martin & Galand, Marina [Vis alle 13 forfattere av denne artikkelen] (2017). Erratum: Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA (Monthly Notices of the Royal Astronomical Society (2017) 469:3 (S252-S261) DOI: 10.1093/mnras/stx1491). Monthly notices of the Royal Astronomical Society. ISSN 0035-8711. 469, s. S804–S804. doi: 10.1093/mnras/stx3069. Fulltekst i vitenarkiv
• Miloch, Wojciech Jacek; Yang, Lei; Paulsson, Joakim John Paul; Wedlund, Cyril Simon; Odelstad, Elias & Edberg, Niklas [Vis alle 8 forfattere av denne artikkelen] (2016). Early Evolution of Comet 67P Studied with the RPC-LAP onboard Rosetta. Fulltekst i vitenarkiv

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