Search Publications

Constraining the Positive Ion Composition in Saturn's Lower Ionosphere with the Effective Recombination Coefficient
DOI: 10.3847/PSJ/abd6e9 Bibcode: 2021PSJ.....2...39D

Vigren, Erik; Wahlund, Jan-Erik; Dreyer, Joshua +4 more

The present study combines Radio and Plasma Wave Science/Langmuir Probe and Ion and Neutral Mass Spectrometer data from Cassini's last four orbits into Saturn's lower ionosphere to constrain the effective recombination coefficient α300 from measured number densities and electron temperatures at a reference electron temperature of 300 K.…

2021 The Planetary Science Journal
Cassini 4
Modeling of CO Rovibrational Line Emission of HD 141569
DOI: 10.1088/1538-3873/ac21a2 Bibcode: 2021PASP..133j4402J

Najita, Joan R.; Brittain, Sean D.; Carr, John S. +1 more

HD 141569 is a Herbig Ae/Be star that straddles the boundary between the transition disks and debris disks. It is a low dust mass disk that reveals numerous structural elements (e.g., gaps and rings) that may point to young planets. It also exhibits a reservoir of CO gas observed at both millimeter and IR wavelengths. Previous observations reporte…

2021 Publications of the Astronomical Society of the Pacific
Gaia 4
Suzaku detection of solar wind charge exchange emission from a variety of highly ionized ions in an interplanetary coronal mass ejection
DOI: 10.1093/pasj/psab015 Bibcode: 2021PASJ...73..504A

Katsuda, Satoru; Ezoe, Yuichiro; Yoneyama, Tomokage +8 more

X-ray emission generated through solar-wind charge exchange (SWCX) is known to contaminate X-ray observation data, the amount of which is often significant or even dominant, particularly in the soft X-ray band, when the main target consists of comparatively weak diffuse sources, depending on the space weather during the observation. In particular,…

2021 Publications of the Astronomical Society of Japan
Suzaku 4
First year of coordinated science observations by Mars Express and ExoMars 2016 Trace Gas Orbiter
DOI: 10.1016/j.icarus.2020.113707 Bibcode: 2021Icar..35313707C

Gondet, B.; Ristic, B.; López-Valverde, M. A. +12 more

Two spacecraft launched and operated by the European Space Agency are currently performing observations in Mars orbit. For >15 years Mars Express has been conducting global surveys of the surface, the atmosphere and the plasma environment of the Red Planet. The Trace Gas Orbiter, the first element of the ExoMars programme, began its science pha…

2021 Icarus
ExoMars-16 MEx 4
Venus's induced magnetosphere during active solar wind conditions at BepiColombo's Venus 1 flyby
DOI: 10.5194/angeo-39-811-2021 Bibcode: 2021AnGeo..39..811V

Miyoshi, Yoshizumi; Plaschke, Ferdinand; Futaana, Yoshifumi +23 more

Out of the two Venus flybys that BepiColombo uses as a gravity assist manoeuvre to finally arrive at Mercury, the first took place on 15 October 2020. After passing the bow shock, the spacecraft travelled along the induced magnetotail, crossing it mainly in the YVSO direction. In this paper, the BepiColombo Mercury Planetary Orbiter Mag…

2021 Annales Geophysicae
BepiColombo 4
The dynamics of the broad-line region in NGC 3227
DOI: 10.1093/mnras/staa3005 Bibcode: 2021MNRAS.500..786D

Devereux, Nick

Archival Hubble Space Telescope (HST) observations of the Seyfert 1 nucleus of NGC 3227 obtained with the Space Telescope Imaging Spectrograph (STIS) are re-examined in order to constrain a viable photoionization model for the broad-line region (BLR). The results imply that the BLR is a partially ionized, dust-free, spherical shell that is collaps…

2021 Monthly Notices of the Royal Astronomical Society
eHST 4
Finding SEIS North on Mars: Comparisons Between SEIS Sundial, Inertial and Imaging Measurements and Consequences for Seismic Analysis
DOI: 10.1029/2020EA001286 Bibcode: 2021E&SS....801286S

Lognonné, P.; Banerdt, W. B.; Golombek, M. P. +10 more

In this paper, we present the results obtained in the determination of the true north direction on Mars by using a gnomon on the InSight mission and compare the measurements with either the North determination from the Inertial Measurement Unit and imaging analysis. The obtained measurement has been used to populate the SEIS orientation informatio…

2021 Earth and Space Science
MEx 4
Evaluating Pointing Strategies for Future Solar Flare Missions
DOI: 10.1007/s11207-021-01896-0 Bibcode: 2021SoPh..296..153I

Ireland, Jack; Christe, Steven D.; Inglis, Andrew R. +1 more

Solar flares are events of intense scientific interest. Although certain solar conditions are known to be associated with flare activity, the exact location and timing of an individual flare on the Sun cannot as yet be predicted with certainty. Missions whose science objectives depend on observing solar flares must often make difficult decisions o…

2021 Solar Physics
SOHO 4
Application of clustering algorithm to wide stellar pairs for unsupervised search of parts of disrupting clusters
DOI: 10.1515/astro-2021-0025 Bibcode: 2021OAst...30..191S

Kovaleva, Dana; Sapozhnikov, Sergei

We introduce the application of the clustering algorithm to the preliminary compiled list of probable wide pairs of co-moving stars. The main aim of such development is a possibility of unsupervised blind search of coeval loose stellar structures over significant regions in space. Using Gaia EDR3 data, we investigated the application of the method…

2021 Open Astronomy
Gaia 4
Small-scale topographic irregularities on Phobos: image and numerical analyses for MMX mission
DOI: 10.1186/s40623-021-01463-8 Bibcode: 2021EP&S...73..213T

Michel, Patrick; Miyamoto, Hideaki; Takemura, Tomohiro +2 more

The mothership of the Martian Moons eXploration (MMX) will perform the first landing and sampling on the surface of Phobos. For the safe landing, the 2.1-m-wide mothership of the MMX should find a smooth surface with at most 40 cm topographic irregularity, however, whose abundance or even existence is not guaranteed based on current knowledge. We …

2021 Earth, Planets and Space
MEx 4