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Marsis on-board software requirements for upgrade
Get PDFThe Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) is an instrument for subsurface remote sensing of the Mars planet. Since its debut, many successful observations have been carried out. At this point of this fruitful mission, having acquired a good knowledge of the Mars environment, it is now necessary to improve the instrument science performances, mitigating some limitations of the on-board SW, that were required at the beginning of the mission, but which were proven to be excessive and above all limiting. The main purpose of this document is to define the requirements necessary to update the on-board SW, in order to add two new improved operative modes to the ones already in use. It is worth noting that, the existing operative modes will remain unchanged and can continue to be used after loading the updated SW. The first new operative mode (SSM) is related to the observation of Mars. It will be similar to the existing main dual channel sub surface mode (SS3). The processing for the first operative channel will remain unchanged, while calculations on the second channel will be modified to extract the most significant data from the full raw data set, discarding what is meaningless or providing poor scientific contribution. The new second operative mode (SSP), will be designed to optimize above all the observation of Phobos, which was not originally thought as a target for MARSIS, this means that a very complex on-board SW configuration is required, in order to force the radar to work properly even in this situation. Moreover, actual Phobos observation makes use of valuable SC resources for storing high quantity of useless data, that cannot be eliminated without modifications of MARSIS SW. The new operative mode will take care of removing these unnecessary data. It will also optimize adaptively the Receiver Gain during the flyby, thereby improving the dynamic range of the receiver of the recorded Science Data. At the same time data-rate on the SC OBDH bus will be strongly reduced, allowing the possibility for MARSIS, PFS and SPICAM to operate simultaneously
Progettazione e realizzazione del nuovo percorso storico-divulgativo multimediale della specola M. Hack
Get PDFNel rapporto tecnico viene descritta la progettazione e realizzazione della riqualificazione del piano terra della Specola M. Hack di Basovizza dell'Osservatorio Astronomico di Trieste, dedicata alle attività con pubblico e scuole, e la conseguente ripresa delle attività di divulgazione e osservazione al telescopio.
OATs ha riqualificato la mostra storica presente dal 1998 al piano terra delle Specola, realizzando un moderno percorso divulgativo storico-scientifico innovativo, ricco di installazioni digitali e contenuti
virtuali che affiancano gli strumenti storici esposti, per un’esperienza ricca di novità, immersiva
e coinvolgente.https://www.oats.inaf.it/images/stories/RassegnaStampa/20220607_Piccolo_Hack100.pdf
https://www.oats.inaf.it/images/stories/RassegnaStampa/20220607_Primorki_Hack100.pd
Timing Analysis of the 2022 Outburst of SAX J1808.4-3658: Hints of Orbital Decay
Get PDFWe present a pulse timing analysis of NICER observations of the accreting millisecond X-ray pulsar SAX J1808.4−3658 during the outburst that started on 2022 August 19. Similar to previous outbursts, after decaying from a peak luminosity of ≃1 × 1036 erg s−1 in about a week, the pulsar entered a ∼1 month long reflaring stage. Comparison of the average pulsar spin frequency during the outburst with those previously measured confirmed the long-term spin derivative of Hz s−1, compatible with the spin-down torque of a ≈1026 G cm3 rotating magnetic dipole. For the first time in the last twenty years, the orbital phase evolution shows evidence for a decrease of the orbital period. The long-term behavior of the orbit is dominated by an ∼11 s modulation of the orbital phase epoch consistent with a ∼21 yr period. We discuss the observed evolution in terms of a coupling between the orbit and variations in the mass quadrupole of the companion star
Spectral reflectance properties of nontronite exposed to Mars-like surface conditions and low-temperature heating (<300 °C)
No full textThe Orion-Taurus ridge: a synchrotron radio loop at the edge of the Orion-Eridanus superbubble
Get PDFLarge-scale synchrotron loops are recognized as the main source of diffuse
radio-continuum emission in the Galaxy at intermediate and high Galactic
latitudes. Their origin, however, remains rather unexplained. Using a
combination of multi-frequency data in the radio band of total and polarized
intensities, for the first time in this letter, we associate one arc --
hereafter, the Orion-Taurus ridge -- with the wall of the most prominent
stellar-feedback blown shell in the Solar neighborhood, namely the
Orion-Eridanus superbubble. We traced the Orion-Taurus ridge using 3D maps of
interstellar dust extinction and column-density maps of molecular gas, . We found the Orion-Taurus ridge at a distance of 400\,pc, with a
plane-of-the-sky extent of \,pc. Its median value is
cm. Thanks to the broadband
observations below 100 MHz of the Long Wavelength Array, we also computed the
low-frequency spectral-index map of synchrotron emissivity, , in the
Orion-Taurus ridge. We found a flat distribution of with a median value
of that we interpreted in terms of depletion of
low-energy ( GeV) cosmic-ray electrons in recent supernova remnants (
- yrs). Our results are consistent with plane-of-the-sky magnetic-field
strengths in the Orion-Taurus ridge larger than a few tens of G (G). We report the first detection of diffuse synchrotron emission from
cold-neutral, partly molecular, gas in the surroundings of the Orion-Eridanus
superbubble. This observation opens a new perspective to study the multiphase
and magnetized interstellar medium with the advent of future high-sensitivity
radio facilities, such as the C-Band All-Sky Survey and the Square Kilometre
Array
Future space experiment platforms for astrobiology and astrochemistry research
Get PDFSpace experiments are a technically challenging but a scientifically important part of astrobiology and astrochemistry research. The International Space Station (ISS) is an excellent example of a highly successful and long-lasting research platform for experiments in space, that has provided a wealth of scientific data over the last two decades. However, future space platforms present new opportunities to conduct experiments with the potential to address key topics in astrobiology and astrochemistry. In this perspective, the European Space Agency (ESA) Topical Team Astrobiology and Astrochemistry (with feedback from the wider scientific community) identifies a number of key topics and summarizes the 2021 “ESA SciSpacE Science Community White Paper” for astrobiology and astrochemistry. We highlight recommendations for the development and implementation of future experiments, discuss types of in situ measurements, experimental parameters, exposure scenarios and orbits, and identify knowledge gaps and how to advance scientific utilization of future space-exposure platforms that are either currently under development or in an advanced planning stage. In addition to the ISS, these platforms include CubeSats and SmallSats, as well as larger platforms such as the Lunar Orbital Gateway. We also provide an outlook for in situ experiments on the Moon and Mars, and welcome new possibilities to support the search for exoplanets and potential biosignatures within and beyond our solar system
Manuale operativo Titulus 5
Get PDFIl sistema di gestione documentale Titulus sta per passare alla versione 5 interamente rinnovata nell'interfaccia e in alcune funzioni. La presente guida operativa serve per orientare l'utente nel passaggio alla nuova version
X-ray polarimetry and spectroscopy of the neutron star low-mass X-ray binary GX 9+9: An in-depth study with IXPE and NuSTAR
Get PDFWe report on a comprehensive analysis of simultaneous X-ray polarimetric and spectral data of the bright atoll source GX 9+9 with the Imaging X-ray Polarimetry Explorer (IXPE) and NuSTAR. The source is significantly polarized in the 4-8 keV band, with a degree of 2.2% ± 0.5% (uncertainty at the 68% confidence level). The NuSTAR broad-band spectrum clearly shows an iron line, and is well described by a model including thermal disc emission, a Comptonized component, and reflection. From a spectro-polarimetric fit, we obtain an upper limit to the polarization degree of the disc of 4% (at the 99% confidence level), while the contribution of Comptonized and reflected radiation cannot be conclusively separated. However, the polarization is consistent with resulting from a combination of Comptonization in a boundary or spreading layer, plus reflection off the disc, which significantly contributes in any realistic scenario