Ricerc@Sapienza

Time Difference of Arrival (TDOA) networks could support spacecraft orbit determination or near-space (launcher and suborbital) vehicle tracking for an increased number of satellite launches and space missions in the near future. The evaluation of the geometry of TDOA networks could involve the dilution of precision (DOP), but this parameter is related to a single position of the target, while the positioning accuracy of the network with targets in the whole celestial vault should be evaluated.

Sixth generation will exploit satellite, aerial, and terrestrial platforms jointly to improve radio access capability and unlock the support of on-demand edge cloud services in three-dimensional (3D) space, by incorporating mobile edge computing (MEC) functionalities on aerial platforms and low-orbit satellites. This will extend the MEC support to devices and network elements in the sky and forge a space-borne MEC, enabling intelligent, personalized, and distributed on-demand services.

Centromeres are highly specialized chromatin domains that enable chromosome segregation and orchestrate faithful cell division. Human centromeres are composed of tandem arrays of ?-satellite DNA, which spans up to several megabases. Little is known about the mechanisms that maintain integrity of the long arrays of ?-satellite DNA repeats. Here, we monitored centromeric repeat stability in human cells using chromosome-orientation fluorescent in situ hybridization (CO-FISH).

Data from the CYGNSS mission, originally conceived to monitor tropical cyclones, are being investigated here for land applications as well. In this paper, a methodology for soil moisture (SM) retrieval from CYGNSS data is presented. The approach derives Level 3 gridded daily SM estimations, over the latitudinal band covered by CYGNSS, at a resolution of 36 km × 36 km, using the CYGNSS reflectivity over land, coupled with ancillary vegetation and roughness information from the SMAP mission.

The paper describes the design and development of an autonomous, low-cost, lowpower, low-mass attitude sensor, that requires no computational resources from the On-Board Computer. Application domain is small satellites (micro- and nano-satellites) the vast majority of which does not have a precision attitude determination and control, due to excessive cost, weight, volume and energy demand requirements, hard to meet in general when satellites have such small dimensions.

A previous study concerning the characterization of a CuCrZr alloy, considered as a possible candidate for the construction of passive satellites while highlighting some critical issues such as low hardness and elastic modulus, showed very interesting characteristics of toughness evaluated with preliminary tests on Charpy specimens and tensile tests. Considering that this alloy finds applications within the ITER project, an international program of great interest, it seems important to characterize many aspects of the alloy.