Search Publications

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
Identification of Single Spectral Lines in Large Spectroscopic Surveys Using UMLAUT: an Unsupervised Machine-learning Algorithm Based on Unbiased Topology
DOI: 10.3847/1538-4365/ac250c Bibcode: 2021ApJS..257...67B

Rodighiero, G.; Vaccari, M.; Battisti, A. +19 more

The identification of an emission line is unambiguous when multiple spectral features are clearly visible in the same spectrum. However, in many cases, only one line is detected, making it difficult to correctly determine the redshift. We developed a freely available unsupervised machine-learning algorithm based on unbiased topology (UMLAUT) that …

2021 The Astrophysical Journal Supplement Series
eHST 4
Analysis of Type II and Type III Radio Bursts Associated with SEPs from Non-Interacting/Interacting Radio-Loud CMEs
DOI: 10.1007/s10511-021-09693-0 Bibcode: 2021Ap.....64..327K

Feng, Li; Prakash, O.; Shanmugaraju, A. +4 more

We analyze radio bursts observed in events with interacting/non-interacting CMEs that produced major SEPs (Ip > 10 MeV) from April 1997 to December 2014. We compare properties of meter (m), decahectometer (DH) type II and DH type III bursts, and time lags for interacting-CME-associated (IC) events and non-interacting-CME-associated (…

2021 Astrophysics
SOHO 4
Morphological Transformation and Star Formation Quenching of Massive Galaxies at 0.5 ≤ z ≤ 2.5 in 3D-HST/CANDELS
DOI: 10.3847/1538-4357/ac2817 Bibcode: 2021ApJ...923...46L

Fang, Guanwen; Gu, Yizhou; Yuan, Qirong +4 more

To figure out the effect of stellar mass and local environment on morphological transformation and star formation quenching in galaxies, we use the massive (M * ≥ 1010 M ) galaxies at 0.5 ≤ z ≤ 2.5 in five fields of 3D-HST/CANDELS. Based on the UVJ diagnosis and the possibility of possessing a spheroid, our sample…

2021 The Astrophysical Journal
eHST 4
SP_Ace v1.4 and the new GCOG library for deriving stellar parameters and elemental abundances
DOI: 10.1051/0004-6361/202038973 Bibcode: 2021A&A...645A..35B

Vallenari, A.; Lucatello, S.; Boeche, C.

Context. Ongoing and future massive spectroscopic surveys will collect very large numbers (106-107) of stellar spectra that need to be analyzed. Highly automated software is needed to derive stellar parameters and chemical abundances from these spectra.
Aims: We present the new version of SP_Ace (Stellar Parameters And C…

2021 Astronomy and Astrophysics
Gaia 4