Search Publications
Dynamic response of the Martian ionosphere to an interplanetary shock: Mars Express and MAVEN observations
Gurnett, D. A.; Halekas, J. S.; Kopf, A. J. +10 more
Multipoint observations from the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on board Mars Express and the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission reveal a dynamic response of the Martian ionosphere to abrupt variations in the upstream solar wind plasma. On 2 February 2017, MAVEN, located upstream …
Long-Term Variability of Jupiter's Magnetodisk and Implications for the Aurora
Bunce, Emma J.; Clarke, John T.; Vogt, Marissa F. +2 more
Observations of Jupiter's UV auroral emissions collected over several years show that the ionospheric positions of the main emission and the Ganymede footprint can vary by as much as 3° in latitude. One explanation for this shift is a change of Jupiter's current sheet current density, which would alter the amount of field line stretching and displ…
AGN Activity in Nucleated Galaxies as Measured by Chandra
Baldassare, Vivienne F.; Gültekin, Kayhan; Gnedin, Oleg Y. +4 more
Motivated by theoretical expectations that nuclear star clusters (NSCs) in galactic centers may provide a favorable environment for supermassive black holes to form and/or efficiently grow, we set out to measure the fraction of nearby nucleated galaxies that also host an active galactic nucleus. We targeted a distance-limited sample of 98 objects …
Characterization of dust aggregates in the vicinity of the Rosetta spacecraft
Jorda, L.; Lamy, P. L.; Lara, L. M. +49 more
In a Rosetta/OSIRIS imaging activity in 2015 June, we have observed the dynamic motion of particles close to the spacecraft. Due to the focal setting of the OSIRIS wide angle camera, these particles were blurred, which can be used to measure their distances to the spacecraft. We detected 109 dust aggregates over a 130 min long sequence, and find t…
Dust in Clusters: Separating the Contribution of Galaxies and Intracluster Media
López-Corredoira, M.; Gutiérrez, C. M.
We have analyzed a sample of 327 clusters of galaxies, spanning the range of 0.06-0.70 in redshift. Strong constraints on their mean intracluster emission of dust have been obtained using maps and catalogs from the Herschel MerMES project; within a radius of 5 arcmin centered in each cluster, the 95% C.L. limits obtained are 86.6, 48.2, and 30.9 m…
A Heuristic Approach to Remove the Background Intensity on White-light Solar Images. I. STEREO/HI-1 Heliospheric Images
Stenborg, Guillermo; Howard, Russell A.
White-light coronal and heliospheric imagers observe scattering of photospheric light from both dust particles (the F-Corona) and free electrons in the corona (the K-corona). The separation of the two coronae is thus vitally important to reveal the faint K-coronal structures (e.g., streamers, co-rotating interaction regions, coronal mass ejections…
Constraining C III] Emission in a Sample of Five Luminous z = 5.7 Galaxies
Siana, Brian; Fan, Xiaohui; Jiang, Linhua +6 more
Recent observations have suggested that the C III]λ 1907/1909 emission lines could be alternative diagnostic lines for galaxies in the reionization epoch. We use the F128N narrowband filter on the Hubble Space Telescope’s (HST) Wide Field Camera 3 (WFC3) to search for C III] emission in a sample of five galaxies at z = 5.7 in the Subaru Deep Field…
Near-Earth plasma sheet boundary dynamics during substorm dipolarization
Strangeway, Robert J.; Plaschke, Ferdinand; Russell, Christopher T. +29 more
We report on the large-scale evolution of dipolarization in the near-Earth plasma sheet during an intense (AL ~ ‑1000 nT) substorm on August 10, 2016, when multiple spacecraft at radial distances between 4 and 15 RE were present in the night-side magnetosphere. This global dipolarization consisted of multiple short-timescale (a couple o…
Rapid X-ray variability properties during the unusual very hard state in neutron-star low-mass X-ray binaries
Altamirano, D.; Degenaar, N.; Wijnands, R. +2 more
Here, we study the rapid X-ray variability (using XMM-Newton observations) of three neutron-star low-mass X-ray binaries (1RXS J180408.9-342058, EXO 1745-248 and IGR J18245-2452) during their recently proposed very hard spectral state. All our systems exhibit a strong to very strong noise component in their power density spectra (rms amplitudes ra…
Venus's winds and temperatures during the MESSENGER's flyby: An approximation to a three-dimensional instantaneous state of the atmosphere
Clancy, R. T.; Hueso, R.; Sánchez-Lavega, A. +14 more
Even though many missions have explored the Venus atmospheric circulation, its instantaneous state is poorly characterized. In situ measurements vertically sampling the atmosphere exist for limited locations and dates, while remote sensing observations provide only global averages of winds at altitudes of the clouds: 47, 60, and 70 km. We present …