2016, Contributo in atti di convegno, ENG
Pardini C.; Anselmo L.
Uncontrolled reentries of sizable space objects are becoming of growing concern due to the increase of space activities around the Earth and population on the ground. After providing an updated review of various aspects of the problem, this paper presents the exemplar case of Progress-M 27M, whose control was lost immediately after launch, on April 28, 2015, and which reentered on May 8. As in similar previous occurrences, the Space Flight Dynamics Laboratory of ISTI/CNR, in Pisa, was in charge of reentry predictions for the Italian civil protection authorities and space agency. The first prediction was issued in the morning of April 30, in the morning of May 7 the only potentially risky reentry trajectory over central Italy was identified, and in the afternoon of May 7, about 12 hours before the actual reentry, any residual risk for Europe and Italy was finally excluded.
2016, Presentazione, ENG
Pardini C.; Anselmo L.
Review of the ISTI-CNR activity carried out for the re-entry campaigns in 2015: Progress-M 27M & IADC test object CZ-2D second stage (2014-051C).
2015, Altro prodotto, ENG
Pardini, C.; Anselmo L.
Presentation of the ISTI-CNR approach to the real time assessment of spatial and temporal risk windows for uncontrolled satellite reentries.
2015, Contributo in volume, ITA
Pardini C.; Anselmo L.
In order to meet the specific requirements of civil protection authorities, since 2003 a set of tailored products has been developed and applied in Italy to define, a few days ahead of re-entry and in wide areas of interest, risk zones and corresponding alert time windows in the event of an uncontrolled satellite decay leading to undue debris impact hazard on the ground and in the overlying airspace. Based on the general properties of re-entries from nearly circular decaying orbits, on the results of detailed fragmentation analyses, when available, on standard re-entry prediction outputs, on specific simulations of endo-atmospheric debris dynamics, and on the basics of orbital motion with respect to the Earth, accurate re-entry tracks over the region(s) of interest are determined, with sufficiently conservative ground safety swaths, accounting for the sources of cross-track debris dispersion, and associated risk time windows, depending on debris flight time dispersion and residual trajectory along-track uncertainties. With the approaching re-entry and the consequent shrinking of the global uncertainty window, some of the risk zones and time windows identified in advance can be progressively discarded, leaving at most, until the end, one re-entry opportunity, but more often none, over a region the size of Italy. These products are easy to understand and are timely, accurate, unambiguous and remarkably stable, all qualities that render them particularly suitable for civil protection applications.
2015, Contributo in atti di convegno, ENG
Pardini C.; Anselmo L.
The uncommon nature of the GOCE reentry campaign, sharing an uncontrolled orbital decay with a finely controlled attitude along the atmospheric drag direction, made the reentry predictions for this satellite an interesting case study, especially because nobody was able to say a priori if and when the attitude control would have failed, leading to an unrestrained tumbling and a sudden variation of the orbital decay rate. As in previous cases, ISTI/CNR was in charge of reentry predictions for the Italian civil protection authorities, monitoring also the satellite decay in the frame of an international reentry campaign promoted by the Inter-Agency Space Debris Coordination Committee (IADC). Due to the peculiar nature of the GOCE reentry, the definition of reliable uncertainty windows was not easy, especially considering the critical use of this information for civil protection evaluations. However, after an initial period of test and analysis, reasonable and conservative criteria were elaborated and applied, with good and consistent results through the end of the reentry campaign. In the last three days of flight, reentries were simulated over Italy to obtain quite accurate ground tracks, debris swaths and air space crossing time windows associated with the critical passes over the national territory still included in the global uncertainty windows.
2015, Presentazione, ENG
Pardini C.; Anselmo L.
After having introduced satellite re-entry statistics, the presentation details the products developed over the years at ISTI-CNR for civil protection applications.
2011, Presentazione, ENG
Pardini, Carmen ; Anselmo, Luciano
The results obtained by ISTI/CNR during the IADC reentry test campaign 2010-1 are presented and compared with the predictions of the other participating agencies.