Low Cost Station Keeping Maneuvers for a Small-Satellites Constellation in TUNDRA Orbits

A constellation of three small satellites placed, in highly inclined geosynchronous eccentric orbits equally spaced, can provide a continuous coverage of a service zone at high latitudes. Satellites on such orbits (TUNDRA) will spend most of the time around the apogee and each satellite of the constellation is required to be at a certain position in the orbit at a fixed time interval, in order to keep the constellation synchronism, which is requested by the user\u27s antenna to have at switch-over time an isopower signal. To counteract the orbit perturbations (mainly due to lunisolar effects), that do not preserve the subtract longitude and synchronism, a low cost maneuvers strategy is proposed. These maneuvers are designed to control both the principal requirements (longitude and synchronism) by adjusting only the semimajor axis (in-plane maneuvers). Since perigee burns are more economical than apogee burns only the apogee radius is adjusted. The evolution of the orbit parameters with a typical sequence of maneuvers is examined including the effects of the moon, sun and a reduced (forth-order) Earth potential model. The effects of the atmospheric drag have not been taken into account due to the high perigee altitude. The maneuvers strategy proposed seems to be very promising in terms of delta-V. This result could yield a favorable opportunity in the use of small satellites for long duration missions (e.g. 5-7 years)

The Italian Approach to Small Satellites for Low Cost Access to Space Developments

Several technological institutions and scientific center are presently forbidden to access space exploration, because of the high costs involved with satellite development and launch. ITALSPAZIO has performed several studies directed toward the minimization of such costs. Possible design approaches are: use of a small bus capable to fly at marginal cost on expendable launch vehicles by paying delta-costs when passing from one launcher class to the upper next of the same launcher, (an example is constituted by the ARIANE IV when passing from AIRANE 40 to ARIANE 42s); use of left-over launcher capacities; use of subsystems and equipment’s developed for the two cases above, but using lower cost launcher

'To school of prevention: the vaccinations', project in the ASL Roma 4

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The First Vega Ride-Share Mission Flight

The first European ride-share mission will be carried out by the Vega launch system in September 2019. The VEGA PoC (Proof of Concept) flight using the SSMS (Small Satellite Mission Service) hardware was conceived in the context of ESA LLL Initiative. This paper reports on the highlights of the preparation of the first European rideshare mission with Vega launcher and on the development of the related launch system. Based on Vega flights accumulated experience, the development of multi-Payload mission concept started from analysis of the activities currently foreseen to fly a single payload mission adapted to the needs of multi payload rideshare missions. After evaluation of impacts in terms of technical feasibility, missioning schedule and related programmatic and cost elements for the missioning of the Light Sats launch service, the implementation phase was initiated and description of its major tasks is the focus of this paper. The described hardware development and processes to reach SSMS PoC flight using the Vega launch system, are the first step towards the ultimate goal of a finally optimized process for Light Sats ride-share missions applicable to all European launchers

Oncoplastic and reconstructive surgery in SENONETWORK Italian breast centers: lights and shadows

Highlights: • Despite the significance of oncoplastic procedure, an italian database is lacking. • Senonetwork established a multidisciplinary survey to assess their safety and efficacy. • Reconstructive outcomes were positive across low and high-volume centers. • After mastectomy, implant-based techniques are common. DTI reconstruction is advantageuos. • This contributes to the global understanding of effective strategies against breast cancer

Topographic mapping of the Moon via a radar system

special issue on “Advances in Remote Sensing