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Qatar Exoplanet Survey: Qatar-8b, 9b, and 10b—A Hot Saturn and Two Hot Jupiters
DOI: 10.3847/1538-3881/ab19bc Bibcode: 2019AJ....157..224A

Bieryla, Allyson; Latham, David W.; Esquerdo, Gilbert A. +26 more

In this paper we present three new extrasolar planets from the Qatar Exoplanet Survey. Qatar-8b is a hot Saturn, with M P = 0.37 M J and R P = 1.3 R J, orbiting a solar-like star every P orb = 3.7 days. Qatar-9b is a hot Jupiter with a mass of M P = 1.2 M J and a radius o…

2019 The Astronomical Journal
Gaia 14
Jensen-Shannon Complexity Measurements in Solar Wind Magnetic Field Fluctuations
DOI: 10.3847/1538-4357/aafda4 Bibcode: 2019ApJ...872...59W

Kivelson, Margaret G.; Weygand, James M.

Turbulent magnetic field fluctuations in the solar wind have been extensively investigated, but few studies have analyzed their complexity. Jensen-Shannon complexity maps of time series data provide a mathematical tool that can characterize fluctuations in laboratory experiments as stochastic, chaotic, or periodic phenomena. We apply this recently…

2019 The Astrophysical Journal
Ulysses 14
On the Source Position and Duration of a Solar Type III Radio Burst Observed by LOFAR
DOI: 10.3847/1538-4357/ab458f Bibcode: 2019ApJ...885..140Z

Kontar, Eduard P.; Zhang, PeiJin; Yu, SiJie +1 more

The flux of solar type III radio bursts have a time profile of rising and decay phases at a given frequency, which has been actively studied since the 1970s. Several factors that may influence the duration of a type III radio burst have been proposed. In this work, to study the dominant cause of the duration, we investigate the source positions of…

2019 The Astrophysical Journal
PROBA-2 14
First Radial Velocity Results From the MINiature Exoplanet Radial Velocity Array (MINERVA)
DOI: 10.1088/1538-3873/ab33c5 Bibcode: 2019PASP..131k5001W

Swift, Jonathan J.; Berlind, Perry; Calkins, Michael L. +52 more

The MINiature Exoplanet Radial Velocity Array (MINERVA) is a dedicated observatory of four 0.7 m robotic telescopes fiber-fed to a KiwiSpec spectrograph. The MINERVA mission is to discover super-Earths in the habitable zones of nearby stars. This can be accomplished with MINERVA’s unique combination of high precision and high cadence over long tim…

2019 Publications of the Astronomical Society of the Pacific
Gaia 14
SOFIA/FORCAST resolves 30-40 µm extended dust emission in nearby active galactic nuclei
DOI: 10.1093/mnras/sty3338 Bibcode: 2019MNRAS.483.3404F

Togi, Aditya; Alonso-Herrero, Almudena; Fuller, Lindsay +7 more

We present arcsecond-scale observations of the active galactic nuclei (AGNs) of seven nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the 31.5 and 37.1 µm filters of the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We isolate unresolved emission from the torus and fi…

2019 Monthly Notices of the Royal Astronomical Society
eHST 14
Multiwavelength observations of the EUV variable metal-rich white dwarf GD 394
DOI: 10.1093/mnras/sty3218 Bibcode: 2019MNRAS.483.2941W

Redfield, Seth; Casewell, Sarah L.; Burleigh, Matthew R. +13 more

We present new Hubble Space Telescope (HST) ultraviolet and ground-based optical observations of the hot, metal-rich white dwarf GD 394. Extreme-ultraviolet (EUV) observations in 1992-1996 revealed a 1.15 d periodicity with a 25 per cent amplitude, hypothesized to be due to metals in a surface accretion spot. We obtained phase resolved HST/Space T…

2019 Monthly Notices of the Royal Astronomical Society
Gaia eHST 14
Superstrong photospheric magnetic fields in sunspot penumbrae
DOI: 10.1051/0004-6361/201834083 Bibcode: 2019A&A...631A..99S

Solanki, S. K.; Lagg, A.; van Noort, M. +2 more

Context. Recently, there have been some reports of unusually strong photospheric magnetic fields (which can reach values of over 7 kG) inferred from Hinode SOT/SP sunspot observations within penumbral regions. These superstrong penumbral fields are even larger than the strongest umbral fields on record and appear to be associated with supersonic d…

2019 Astronomy and Astrophysics
Hinode 14
Fine-scale structure in cometary dust tails I: Analysis of striae in Comet C/2006 P1 (McNaught) through temporal mapping
DOI: 10.1016/j.icarus.2018.09.013 Bibcode: 2019Icar..319..540P

Morgan, Huw; Jones, Geraint H.; Battams, Karl +5 more

Striated features, or striae, form in cometary dust tails due to an as-yet unconstrained process or processes. For the first time we directly display the formation of striae, at C/2006 P1 McNaught, using data from the SOHO LASCO C3 coronagraph. The nature of this formation suggests both fragmentation and shadowing effects are important in the form…

2019 Icarus
SOHO 14
Polarimetric and Photometric Investigation of the Dark Globule LDN 1225: Distance, Extinction Law, and Magnetic Fields
DOI: 10.3847/1538-4357/ab0a0c Bibcode: 2019ApJ...875...64E

Jose, Jessy; Wang, Jia-Wei; Lai, Shih-Ping +7 more

We present results based on the optical R-band observations of the polarization of 280 stars distributed toward the dark globule LDN 1225. Parallaxes from Gaia data release 2 along with the polarization data of ∼200 stars have been used to (a) constrain the distance of LDN 1225 as 830 ± 83 pc, (b) determine the contribution of interstellar polariz…

2019 The Astrophysical Journal
Gaia 14
Observations of the Venus Dramatic Response to an Extremely Strong Interplanetary Coronal Mass Ejection
DOI: 10.3847/1538-4357/ab14e1 Bibcode: 2019ApJ...876...84X

Xu, Qi; Zhang, Tielong; Rong, Zhaojin +4 more

On 2011 November 5, Venus Express observed the impact of an extremely strong interplanetary coronal mass ejection (ICME) on Venus. As a result, the Venusian induced magnetosphere dramatically fluctuated during the ICME passage: the bow shock was compressed and broadened by the sheath and the body of the ICME, respectively; an atypically strong mag…

2019 The Astrophysical Journal
VenusExpress 14