Search Publications
Polygon pattern geomorphometry on Svalbard (Norway) and western Utopia Planitia (Mars) using high-resolution stereo remote-sensing data
Hauber, E.; Ulrich, M.; Herzschuh, U. +2 more
Polygonal systems formed by thermal contraction cracking are complex landscape features widespread in terrestrial periglacial regions. The manner in which cracking occurs is controlled by various environmental factors and determines dimension, shape, and orientation of polygons. Analogous small-scale features are ubiquitous in Martian mid- and hig…
A Coronal Seismological Study with Streamer Waves
Feng, S. W.; Chen, Y.; Li, B. +4 more
We present a novel method to evaluate the Alfvén speed and the magnetic field strength along the streamer plasma sheet in the outer corona. The method is based on recent observations of streamer waves, which are regarded as the fast kink body mode carried by the plasma sheet structure and generated upon the impact of a fast coronal mass ejection (…
Venus’s Southern Polar Vortex Reveals Precessing Circulation
Erard, S.; Drossart, P.; Piccioni, G. +5 more
Initial images of Venus’s south pole by the Venus Express mission have shown the presence of a bright, highly variable vortex, similar to that at the planet’s north pole. Using high-resolution infrared measurements of polar winds from the Venus Express Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument, we show the vortex to hav…
A new comprehensive 2D model of the point spread functions of the XMM-Newton EPIC telescopes: spurious source suppression and improved positional accuracy
Read, A. M.; Saxton, R. D.; Rosen, S. R. +1 more
Aims: We describe here a new full 2D parameterization of the PSFs of the three XMM-Newton EPIC telescopes as a function of instrument, energy, off-axis angle and azimuthal angle, covering the whole field-of-view (FoV) of the three EPIC detectors. It models the general PSF envelopes, the primary and secondary spokes, their radial dependencies,…
Magnetic effects of the substorm current wedge in a “spread-out wire” model and their comparison with ground, geosynchronous, and tail lobe data
Sergeev, V. A.; Baumjohann, W.; Tsyganenko, N. A. +3 more
Although the substorm current wedge (SCW) is recognized as a basic 3-D current system of the substorm expansion phase, its existing models still do not extend beyond a cartoon-like sketch, and very little is known of how well they reproduce magnetic variations observed in the magnetosphere during substorms. A lack of a realistic quantitative SCW m…
Locally enhanced precipitation organized by planetary-scale waves on Titan
Turtle, Elizabeth P.; Mitchell, Jonathan L.; Ádámkovics, Máté +1 more
Saturn's moon Titan exhibits an active weather cycle that involves methane. Equatorial and mid-latitude clouds can be organized into fascinating morphologies on scales exceeding 1,000km (ref. ). Observations include an arrow-shaped equatorial cloud that produced detectable surface accumulation, probably from the precipitation of liquid methane. An…
Luminous starbursts in the redshift desert at z∼ 1-2: star formation rates, masses and evidence for outflows
Ivison, R. J.; Smail, Ian; Dunlop, J. S. +5 more
We present a spectroscopic catalogue of 40 luminous starburst galaxies at z= 0.7-1.7 (median z= 1.3). 19 of these are submillimetre galaxies (SMGs) and 21 are submillimetre-faint radio galaxies (SFRGs). This sample helps us to fill in the redshift desert at z= 1.2-1.7 in previous studies as well as to probe a lower luminosity population of galaxie…
A new globular cluster black hole in NGC 4472
Kundu, Arunav; Zepf, Stephen E.; Maccarone, Thomas J. +1 more
We discuss CXOU 1229410+075744, a new black hole candidate in a globular cluster in the elliptical galaxy NGC 4472. By comparing two Chandra observations of the galaxy, we find a source that varies by at least a factor of 4, and has a peak luminosity of at least 2 × 1039 erg s-1. As such, the source varies by significantly mo…
Small-scale structures in Saturn's ultraviolet aurora
Bonfond, B.; Gérard, J. -C.; Grodent, D. +3 more
On 26 August 2008, the Ultraviolet Imaging Spectrograph Subsystem (UVIS) instrument onboard the Cassini spacecraft recorded a series of spatially resolved spectra of the northern auroral region of Saturn. Near periapsis, the spacecraft was only five Saturn radii (RS) from the surface and spatially resolved auroral structures as small as…
Asteroseismology of the Transiting Exoplanet Host HD 17156 with Hubble Space Telescope Fine Guidance Sensor
Nelan, Edmund P.; Gilliland, Ronald L.; Christensen-Dalsgaard, Jørgen +5 more
Observations conducted with the Fine Guidance Sensor on the Hubble Space Telescope (HST) providing high cadence and precision time-series photometry were obtained over 10 consecutive days in 2008 December on the host star of the transiting exoplanet HD 17156b. During this time, 1.0 × 1012 photons (corrected for detector dead time) were …