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Crater detection via genetic search methods to reduce image features
Cohen, Joseph Paul; Ding, Wei
Recent approaches to crater detection have been inspired by face detection's use of gray-scale texture features. Using gray-scale texture features for supervised machine learning crater detection algorithms provides better classification of craters in planetary images than previous methods. When using Haar features it is typical to generate thousa…
MIDACO software performance on interplanetary trajectory benchmarks
Schlueter, Martin
A numerical study of the MIDACO optimization software on the well known GTOP benchmark set, published by the European Space Agency (ESA), is presented. The GTOP database provides trajectory models of real-world interplanetary space missions such as Cassini, Messenger or Rosetta. The trajectory models are formulated as constrained nonlinear optimiz…
PlanetServer: Innovative approaches for the online analysis of hyperspectral satellite data from Mars
Rossi, A. P.; Flahaut, J.; Oosthoek, J. H. P. +4 more
PlanetServer is a WebGIS system, currently under development, enabling the online analysis of Compact Reconnaissance Imaging Spectrometer (CRISM) hyperspectral data from Mars. It is part of the EarthServer project which builds infrastructure for online access and analysis of huge Earth Science datasets. Core functionality consists of the rasdaman …
The effective temperatures of O-type stars from UV spectroscopy
Bianchi, Luciana; Garcia, Miriam
We present an analysis of high resolution spectra in the far-UV - UV range (∼905-2000 Å) with non-LTE, spherical, hydrodynamical, line-blanketed models, of three O-type Galactic stars, and derive their photospheric and wind parameters. These data extend previously analyzed samples and fill a gap in spectral type coverage. The combined sample confi…
Hard X-ray continuum from lunar surface: Results from High Energy X-ray spectrometer (HEX) onboard Chandrayaan-1
Banerjee, D.; Sreekumar, P.; Sudhakar, M. +10 more
The High Energy X-ray spectrometer (HEX) on Chandrayaan-1 was designed to study the photon emission in the range of 30-270 keV from naturally occurring radioactive decay of 238U and 232Th series nuclides from the lunar surface. The primary objective of HEX was to study the transport of volatiles on the lunar surface using rad…
Testing the asymmetric cone model for halo CMEs using STEREO/SECCHI coronagraphic observations
Michalek, Grzegorz; Nicewicz, Janusz
Space weather is significantly controlled by halo coronal mass ejections (HCMEs) originating close to the central meridian and directing toward the Earth. Unfortunately, coronagraphic observations (especially for HCMEs) are subject to a projection effect which makes it impossible to determine the true radial velocity and width of CMEs. However, th…
Mapping lunar surface chemistry: New prospects with the Chandrayaan-2 Large Area Soft X-ray Spectrometer (CLASS)
Kellett, B. J.; Narendranath, S.; Sreekumar, P. +4 more
Surface chemistry of airless bodies in the solar system can be derived from remote X-ray spectral measurements from an orbiting spacecraft. X-rays from planetary surfaces are excited primarily by solar X-rays. Several experiments in the past have used this technique of X-ray fluorescence for deriving abundances of the major rock forming elements. …
The optical emission lines of type 1 X-ray bright Active Galactic Nuclei
La Mura, G.; Ciroi, S.; Cracco, V. +3 more
A strong X-ray emission is one of the defining signatures of nuclear activity in galaxies. According to the Unified Model for Active Galactic Nuclei (AGN), both the X-ray radiation and the prominent broad emission lines, characterizing the optical and UV spectra of Type 1 AGNs, are originated in the innermost regions of the sources, close to the S…
Characterization of lunar soils through spectral features extraction in the NIR
Mall, U.; Wöhler, C.; Grumpe, A. +2 more
Recently launched hyper-spectral instrumentation with ever-increasing data return capabilities deliver the remote-sensing data to characterize planetary soils with increased precision, thus generating the need to classify the returned data in an efficient way for further specialized analysis and detection of features of interest. This paper invest…
A statistical study of C IV regions in 20 Oe-stars
Popović, L. Č.; Antoniou, A.; Stathopoulos, D. +3 more
In this paper, using the Gauss-Rotation model (GR model), we analyse the UV C IV resonance lines in the spectra of 20 Oe-stars of different spectral subtypes, in order to detect the structure of C IV region. We study the presence and behavior of absorption clouds and analyse their characteristics. From this analysis we can calculate the values of …