Search Publications

On the size distribution of spots within sunspot groups
DOI: 10.1051/0004-6361/202140621 Bibcode: 2021A&A...652A...9M

Solanki, Sami K.; Krivova, Natalie A.; Mandal, Sudip +1 more

The size distribution of sunspots provides key information about the generation and emergence processes of the solar magnetic field. Previous studies of size distribution have primarily focused on either the whole group or individual spot areas. In this paper we investigate the organisation of spot areas within sunspot groups. In particular, we an…

2021 Astronomy and Astrophysics
SOHO 9
Ice-rich landforms of the southern mid-latitudes of Mars: A case study in Nereidum Montes
DOI: 10.1016/j.icarus.2020.114170 Bibcode: 2021Icar..35514170B

Crown, David A.; Berman, Daniel C.; Smith, Isaac B. +1 more

Mapping of Viscous Flow Features (VFFs), a general grouping of ice-rich flow features that includes Lobate Debris Aprons (LDA), Concentric Crater Fill (CCF), Lineated Valley Flow (LVF), small lobate flows (i.e., glacier-like flows, or GLFs), and arcuate ridges, in the southern hemisphere of Mars shows a dense concentration in Nereidum Montes, alon…

2021 Icarus
MEx 9
Local Environments of Low-redshift Supernovae
DOI: 10.3847/1538-4357/ac28a2 Bibcode: 2021ApJ...923...86C

Sandstrom, Karin M.; Leroy, Adam K.; Koch, Eric W. +7 more

We characterize the local (2 kpc sized) environments of Type Ia, II, and Ib/c supernovae (SNe) that have recently occurred in nearby (d ≲ 50 Mpc) galaxies. Using ultraviolet (UV; from Galaxy Evolution Explorer) and infrared (IR; from Wide-field Infrared Survey Explorer) maps of 359 galaxies and a sample of 472 SNe, we measure the star formation ra…

2021 The Astrophysical Journal
Gaia 9
Small lobe of comet 67P: Characterization of the Wosret region with ROSETTA-OSIRIS
DOI: 10.1051/0004-6361/202141014 Bibcode: 2021A&A...653A.132F

Sierks, H.; Barucci, M. A.; Fornasier, S. +3 more


Aims: We investigated Wosret, a region located on the small lobe of the 67P/Churyumov-Gerasimenko comet subject to strong heating during the perihelion passage. This region includes the two last landing sites of the Philae lander as well as, notably the final one, Abydos, where the lander performed most of its measurements. We study Wosret in…

2021 Astronomy and Astrophysics
Rosetta 9
Unexpected Short-period Variability in Dwarf Carbon Stars from the Zwicky Transient Facility
DOI: 10.3847/1538-4357/ac157c Bibcode: 2021ApJ...922...33R

Roulston, Benjamin R.; Green, Paul J.; Hermes, J. J. +1 more

Dwarf carbon (dC) stars, main-sequence stars showing carbon molecular bands, are enriched by mass transfer from a previous asymptotic-giant-branch (AGB) companion, which has since evolved to a white dwarf. While previous studies have found radial-velocity variations for large samples of dCs, there are still relatively few dC orbital periods in the…

2021 The Astrophysical Journal
Gaia 9
A study of open clusters Frolov 1 and NGC 7510 using CCD UBV photometry and Gaia DR2 astrometry
DOI: 10.1002/asna.202113837 Bibcode: 2021AN....342..538Y

Bilir, Selçuk; Yontan, Talar; Paunzen, Ernst +6 more

We present reddening, photometric metallicity, age, and distance estimates for the Frolov 1 and NGC 7510 open clusters based on charge‑coupled device (CCD)UBVphotometric andGaiadata. Photometric observations were collected using the 1‑m telescope of the TÜBİTAK National Observatory.Gaiadata release 2 (DR2) proper motion data in the direction of tw…

2021 Astronomische Nachrichten
Gaia 9
Ionospheric plasma energization at Mars during the September 2017 ICME event
DOI: 10.1016/j.pss.2021.105291 Bibcode: 2021P&SS..20505291K

Bhardwaj, Anil; Thampi, R. Satheesh; Thampi, Smitha V. +2 more

During September 2017, the solar active region (AR) 12673 produced several flares and Coronal Mass Ejections (CMEs). On 10 September 2017, a stronger and wider CME was erupted from AR 12673, which was Mars-directed (max. vsw = ~840 km s-1 near 1.5 au). This ICME caused a major space weather event at Mars on 12-13 September. W…

2021 Planetary and Space Science
SOHO 9
The Formation and Lifetime of Outflows in a Solar Active Region
DOI: 10.3847/1538-4357/ac0917 Bibcode: 2021ApJ...917...25B

Polito, Vanessa; Warren, Harry P.; Barczynski, Krzysztof +4 more

Active regions are thought to be one contributor to the slow solar wind. Upflows in EUV coronal spectral lines are routinely observed at their boundaries, and provide the most direct way for upflowing material to escape into the heliosphere. The mechanisms that form and drive these upflows, however, remain to be fully characterized. It is unclear …

2021 The Astrophysical Journal
Hinode IRIS 9
The role of astronomical silicates during a cometary outburst
DOI: 10.1088/1674-4527/21/3/69 Bibcode: 2021RAA....21...69W

Wesołowski, Marcin

This paper presents a new approach to analyzing the change of cometary brightness. In our considerations, we assume that astronomical silicates (dust agglomerates) and gas are present in the coma. This assumption is a consequence of the analysis of the result observed during the Rosetta mission to comet 67P/Churyumov-Gerasimenko (abbreviated 67P/C…

2021 Research in Astronomy and Astrophysics
Rosetta 9
The Dragonfly Wide Field Survey. II. Accurate Total Luminosities and Colors of Nearby Massive Galaxies and Implications for the Galaxy Stellar-mass Function
DOI: 10.3847/1538-4357/abd7f8 Bibcode: 2021ApJ...909...74M

van Dokkum, Pieter; Conroy, Charlie; Abraham, Roberto +8 more

Stellar-mass estimates of massive galaxies are susceptible to systematic errors in their photometry, due to their extended light profiles. In this study, we use data from the Dragonfly Wide Field Survey to accurately measure the total luminosities and colors of nearby massive galaxies. The low surface brightness limits of the survey (µg…

2021 The Astrophysical Journal
Gaia 9