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Ionospheric irregularities associated with horizontal magnetic fields below 200 km altitude are observed at Mars. Plasma density modulations of up to 200% are observed during such events and appear correlated with fluctuations in the magnetic field. The observed fluctuations are likely Doppler shifted and represent spatial structures at length scales of 15-20 km or less. Conditions in the Martian ionosphere below 200 km are synonymous with the terrestrial E region, where ionospheric irregularities have been extensively studied. Interestingly, the irregularities at Mars appear to be electromagnetic in nature, in contrast to the electrostatic nature of irregularities at Earth. It is currently unclear what the primary drivers of these irregularities at Mars are, and further study is needed to explain these important phenomenon within the Martian ionosphere.

We introduce the Keck Osiris Nearby AGN survey (KONA), a new adaptive optics-assisted integralfield spectroscopic survey of Seyfert galaxies. KONA permits at ∼ 0.1 resolution a detailed study of the nuclear kinematic structure of gas and stars in a representative sample of 40 local bona fide active galactic nucleus (AGN). KONA seeks to characterize the physical processes responsible for the coevolution of supermassive black holes and galaxies, principally inflows and outflows. With these IFU data of the nuclear regions of 40 Seyfert galaxies, the KONA survey will be able to study, for the first time, a number of key topics with meaningful statistics. In this paper we study the nuclear K−band properties of nearby AGN. We find that the K−band (2.1 µm) luminosities of the compact Seyfert 1 nuclei are correlated with the hard X-ray luminosities, implying a non-stellar origin for the majority of the continuum emission. The best-fit correlation is logL K = 0.9logL 2−10 keV + 4 over three orders of magnitude in both K−band and X-ray luminosities. We find no strong correlation between 2.1 µm luminosity and hard X-ray luminosity for the Seyfert 2 galaxies. The spatial extent and spectral slope of the Seyfert 2 galaxies indicate the presence of nuclear star formation and attenuating material (gas and dust), which in some cases is compact and in some galaxies extended. We detect coronal-line emission in 36 galaxies and for the first time in five galaxies. Finally, we find 4/20 galaxies that are usually classified as Seyfert 2 based on their optical spectra exhibit a broad component of Brγ emission, and one galaxy (NGC 7465) shows evidence of a double nucleus.

<p> </p> <p>An investigation of the locations where the bulk thermal pressure is balanced by magnetic pressure in the Martian ionosphere is reported on. We present a statistical study in which we characterize the location where the plasma and magnetic pressures are equal to one another. The data, recorded by the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, have been analyzed from the transition altitude in which the ionospheric ions become magnetized, up to an altitude of ~800km. The electron temperature and density measurements for the plasma thermal pressure were made by the Langmuir Probe and Waves (LPW) instrument, and the magnetic field strength for determining the magnetic pressure was measured by the Magnetometer (MAG) instrument. The three major trends in this pressure balance are: (a) the magnetic pressure is always larger, (b) a clear transition at low altitudes from thermal pressure to magnetic pressure is observed, and (c) the dominant pressure is changing back and forth between the two over a range of altitudes. The findings are studied in congruence with orbital parameters of the MAVEN satellite (including solar local time, latitude, location with respect to crustal fields) to divulge possible explanations of the transition between pressures.</p>