Search Publications
Missions
Journals
Publication Years
Probing plasma properties and dynamics inside the Sun
Kosovichev, Alexander G.
Helioseismology experiment MDI on board the SOHO spacecraft has provided tremendous amount of new information about the thermodynamic properties and dynamics of plasma in the Sun’s interior, uncovering remarkable new perspectives for studying complex interactions between turbulent convection, rotation and magnetism below the solar surface, and the…
Ceres: High-resolution imaging with HST and the determination of physical properties
Russell, C. T.; Stern, S. A.; Young, E. F. +4 more
Nine HST orbits have been used to image Ceres using the High Resolution Camera of the Advanced Camera for Surveys. Two hundred and fifty-nine images in three filters (F555W, F330W and F220W) were obtained covering the entire surface. Two visible features are readily apparent, a dark patch and a bright point. The bright spot was suitable for contro…
A new luminous supersoft X-ray source in NGC 300
Schirmer, M.; Wilms, J.; Kendziorra, E. +1 more
Context: .We report the discovery of a new luminous supersoft source,
The Remarkable Far-Ultraviolet Spectrum of FK Comae Berenices: King of Spin
Ayres, Thomas R.; Redfield, Seth; Harper, Graham M. +4 more
A Far Ultraviolet Spectroscopic Explorer (FUSE) pointing on the ultrafast rotating yellow giant FK Comae Berenices (HD 117555; vsini~163 km s-1) recorded emission profiles of C III λ977 (T~8×104 K) and O VI λ1031 (T~3×105 K) that are exceptionally broad and asymmetric, but nearly identical in shape, aside from a bl…
Inference of magnetospheric currents from multipoint magnetic field measurements
Van Allen, James A.
The European Space Agency has deployed four essentially identical spacecraft into similar near-polar eccentric orbits about the Earth. Each of the four spacecraft carries dual three-axis magnetometers. From simultaneous observations of the magnetic field B at the four vertices of the tetrahedral cluster of spacecraft, it is possible to determine ∇…
Identification of the broad solar emission features near 117 nm
Kurucz, R. L.; Avrett, E. H.; Loeser, R.
Wilhelm et al. have recently called attention to the unidentified broad emission features near 117 nm in the solar spectrum. They discuss the observed properties of these features in detail but do not identify the source of this emission. We show that the broad autoionizing transitions of neutral sulfur are responsible for these emission features.…
VI Photometry of Globular Clusters NGC 6293 and NGC 6541: The Formation of the Metal-poor Inner Halo Globular Clusters
Lee, Jae-Woo; Carney, Bruce W.
We present VI photometry of the metal-poor inner halo globular clusters NGC 6293 and NGC 6541 using the WFPC2 on board the Hubble Space Telescope (HST). Our color-magnitude diagrams of the clusters show well-defined blue horizontal-branch populations, consistent with their low metallicities and old ages. NGC 6293 appears to have blue straggler sta…
Matched filters for source detection in the Poissonian noise regime
Stewart, I. M.
A procedure is described for estimating an optimum kernel for the detection by convolution of signals among Poissonian noise. The technique is applied to the detection of X-ray point sources in XMM-Newton data, and is shown to yield an improvement in detection sensitivity of up to 60% over the sliding-box method used in the creation of the 1XMM ca…
Assessment of the Martian gravity field at short wavelength with Mars Express
Pätzold, M.; Rosenblatt, P.; Le Maistre, S. +6 more
The gravity part of the Mars Express Radio Science Experiment consists in measuring gravity data near pericenter above selected target areas of geophysical interest. The low altitude of the Mars Express at pericenter (263-329 km) makes it a very sensitive gravity sensor at small wavelengths which can give new constraints on the local structure of …
Striated drifting auroral kilometric radiation bursts: Possible stimulation by upward traveling EMIC waves
Santolik, O.; Menietti, J. D.; Mutel, R. L. +3 more
We investigate waves observed by the Cluster wideband instrument (WBD) during an orbital conjunction with the Polar spacecraft. During this perigee pass, Polar was at the upper extent of the auroral kilometric radiation (AKR) source region in the Southern Hemisphere nightside auroral region. Cluster was located at higher altitude above this region…