Search Publications
High-angular-resolution stellar imaging with occultations from the Cassini spacecraft - I. Observational technique
Nicholson, Philip D.; Hedman, Matthew M.; Lloyd, James P. +2 more
We present novel observations utilizing the Cassini spacecraft to conduct an observing campaign for stellar astronomy from a vantage point in the outer Solar system. By exploiting occultation events in which Mira passed behind the Saturnian ring plane as viewed by Cassini, parametric imaging data were recovered spanning the near-infrared. From thi…
Retrieval of jovian cloud structure from the Cassini ISS limb-darkening data. I. Continuum scattering phase functions for cloud and haze in the South Tropical Zone
Kasaba, Y.; Sato, T. M.; Satoh, T.
We have deduced the scattering properties of aerosols in the jovian upper troposphere by analyzing imaging data obtained at a wide variety of solar phase angles (4-140°) by the Cassini Imaging Science Subsystem (ISS) Narrow Angle Camera (NAC) during its flyby of Jupiter. The limb-darkening curves along the South Tropical Zone (STrZ) are extracted …
Axis and velocity determination for quasi two-dimensional plasma/field structures from Faraday's law: A second look
Hasegawa, Hiroshi; Swisdak, M.; Sonnerup, Bengt U. Ö. +1 more
We re-examine the basic premises of a single-spacecraft data analysis method, developed by Sonnerup and Hasegawa (2005), for determining the axis orientation and proper frame velocity of quasi two-dimensional, quasi-steady structures of magnetic field and plasma. The method, which is based on Faraday's law, makes use of magnetic and electric field…
Probing IMF using nanodust measurements from inside Saturn's magnetosphere
Kempf, S.; Postberg, F.; Srama, R. +6 more
We present a new concept of monitoring the interplanetary magnetic field (IMF) by using in situ measurements of nanodust stream particles in Saturn's magnetosphere. We show that the nanodust detection pattern obtained inside the magnetosphere resembles those observed in interplanetary space and is associated with the solar wind compression regions…
Energy distribution asymmetry of electron precipitation signatures at Mars
Coates, A. J.; Barabash, S.; Lundin, R. +5 more
The different types of asymmetry observed in the energy distributions of electrons and heavy-ions (M/Q=16-44) during signatures of electron precipitation in the Martian ionosphere have been classified. This has been achieved using the space plasma instrumentation of MEX ASPERA-3 from peri-centre altitude to 2200 km. ASPERA-3 ELS observes signature…
Stray-light correction in 2D spectroscopy
Franz, M.; Schlichenmaier, R.
Context. In solar physics, spectropolarimeters based on Fabry-Pérot interferometers are commonly used for high spatial resolution observations. In the data pipeline, corrections for scattered light may be performed on each narrow band image.
Aims: We elaborate on the effects of stray-light corrections on Doppler maps.
Methods: First, we …
Absolute magnitude calibration for red clump stars
Bilir, S.; Karaali, S.; Yaz Gökçe, E.
We combined the (Ks, J‑Ks) data in Laney et al. (Mon. Not. R. Astron. Soc. 419:1637, 2012) with the V apparent magnitudes and trigonometric parallaxes taken from the Hipparcos catalogue and used them to fit the
The Projects for Onboard Autonomy (PROBA2) Science Centre: Sun Watcher Using APS Detectors and Image Processing (SWAP) and Large-Yield Radiometer (LYRA) Science Operations and Data Products
Berghmans, D.; Seaton, D. B.; Nicula, B. +18 more
The PROBA2 Science Centre (P2SC) is a small-scale science operations centre supporting the Sun observation instruments onboard PROBA2: the EUV imager Sun Watcher using APS detectors and image Processing (SWAP) and Large-Yield Radiometer (LYRA). PROBA2 is one of ESA's small, low-cost Projects for Onboard Autonomy (PROBA) and part of ESA's In-Orbit …
Dust Impact Monitor (DIM) onboard Rosetta/Philae: Comparison of experimental results and the theory behind the experiment
Flandes, Alberto; Krüger, Harald; Loose, Alexander +4 more
The Dust Impact Monitor (DIM) experiment on board the Rosetta spacecraft's lander, Philae, is a cube with three sides covered with piezo-electric (PZT) sensors (total sensitive area: ≈70cm2), aimed at measuring the physical properties of millimetric and sub-millimetric dust particles that move near the surface of comet 67P/Churyumov - G…
New VLT observations of the Fermi pulsar PSR J1048-5832
de Luca, A.; Marelli, M.; Razzano, M. +1 more
PSR J1048-5832 is a Vela-like (P = 123.6 ms; τ ∼ 20.3 kyr) γ-ray pulsar detected by Fermi, at a distance of ∼2.7 kpc and with a rotational energy loss rate dot{E}_SD ∼ 2 × 10^{36} erg s-1. The PSR J1048-5832 field has been observed with the Very Large Telescope (VLT) in the V and R bands. We used these data to determine the colour of th…