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1. Momentum Transfer from the DART Mission Kinetic Impact on Asteroid Dimorphos

Author

Cheng, Andrew F., Agrusa, Harrison F., Barbee, Brent W., Meyer, Alex J., Farnham, Tony L., Raducan, Sabina D., Richardson, Derek C., Dotto, Elisabetta, Zinzi, Angelo, Della Corte, Vincenzo, Statler, Thomas S., Chesley, Steven, Naidu, Shantanu P., Hirabayashi, Masatoshi, Li, Jian-Yang, Eggl, Siegfried, Barnouin, Olivier S., Chabot, Nancy L., Chocron, Sidney, Collins, Gareth S., Daly, R. Terik, Davison, Thomas M., DeCoster, Mallory E., Ernst, Carolyn M., Ferrari, Fabio, Graninger, Dawn M., Jacobson, Seth A., Jutzi, Martin, Kumamoto, Kathryn M., Luther, Robert, Lyzhoft, Joshua R., Michel, Patrick, Murdoch, Naomi, Nakano, Ryota, Palmer, Eric, Rivkin, Andrew S., Scheeres, Daniel J., Stickle, Angela M., Sunshine, Jessica M., Trigo-Rodriguez, Josep M., Vincent, Jean-Baptiste, Walker, James D., Wünnemann, Kai, Zhang, Yun, Amoroso, Marilena, Bertini, Ivano, Brucato, John R., Capannolo, Andrea, Cremonese, Gabriele, Dall'Ora, Massimo, Deshapriya, Prasanna J. D., Gai, Igor, Hasselmann, Pedro H., Ieva, Simone, Impresario, Gabriele, Ivanovski, Stavro L., Lavagna, Michèle, Lucchetti, Alice, Epifani, Elena M., Modenini, Dario, Pajola, Maurizio, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Poggiali, Giovanni, Rossi, Alessandro, Tortora, Paolo, Zannoni, Marco, and Zanotti, Giovanni

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

The NASA Double Asteroid Redirection Test (DART) mission performed a kinetic impact on asteroid Dimorphos, the satellite of the binary asteroid (65803) Didymos, at 23:14 UTC on September 26, 2022 as a planetary defense test. DART was the first hypervelocity impact experiment on an asteroid at size and velocity scales relevant to planetary defense, intended to validate kinetic impact as a means of asteroid deflection. Here we report the first determination of the momentum transferred to an asteroid by kinetic impact. Based on the change in the binary orbit period, we find an instantaneous reduction in Dimorphos's along-track orbital velocity component of 2.70 +/- 0.10 mm/s, indicating enhanced momentum transfer due to recoil from ejecta streams produced by the impact. For a Dimorphos bulk density range of 1,500 to 3,300 kg/m$^3$, we find that the expected value of the momentum enhancement factor, $\beta$, ranges between 2.2 and 4.9, depending on the mass of Dimorphos. If Dimorphos and Didymos are assumed to have equal densities of 2,400 kg/m$^3$, $\beta$= 3.61 +0.19/-0.25 (1 $\sigma$). These $\beta$ values indicate that significantly more momentum was transferred to Dimorphos from the escaping impact ejecta than was incident with DART. Therefore, the DART kinetic impact was highly effective in deflecting the asteroid Dimorphos., Comment: accepted by Nature

Published
2023
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13. Sky visibility analysis for astrophysical data return maximization in HERMES constellation

Author

Colagrossi, Andrea, Prinetto, Jacopo, Silvestrini, Stefano, and Lavagna, Michèle

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

HERMES is a scientific mission composed of 3U nano-satellites dedicated to the detection and localization of high-energy astrophysical transients, with a distributed space architecture to form a constellation in Earth orbits. The space segment hosts novel miniaturized detectors to probe the X-ray temporal emission of bright events, such as Gamma-Ray Bursts (GRBs), and the electromagnetic counterparts of Gravitational Wave Events (GWEs), playing a crucial role in future multi-messenger astrophysics. During operations, at least three instruments, separated by a minimum distance shall observe a common area of the sky to perform a triangulation of the observed event. An effective detection by the nano-satellite payload is achieved by guaranteeing a beneficial orbital and pointing configuration of the constellation. The design has to cope with the limitations imposed by small space systems, such as the lack of on-board propulsion and the reduced systems budgets. The paper describes the methodologies and the proposed strategies to overcome the mission limitations, while achieving a satisfactory constellation visibility of the sky throughout the mission duration. The mission design makes use of a high-fidelity orbit propagator, combined with an innovative mission analysis tool that estimates the scientific performances of the constellation. The influence of the natural relative motion, which is crucial to achieve an effective constellation configuration without on-board orbit control, is assessed. The presented methodology can be easily extended to any kind of distributed scientific space applications, as well as to constellations dedicated to Earth and planetary observation. In addition, the visibility tool is applicable in the context of the constellation flight dynamics operations, yielding optimized results and pointing plans based on actual satellite orbital positions., Comment: 31 pages, 18 figures, 3 tables. Published in Journal of Astronomical Telescopes, Instruments, and Systems

Published
2020
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23. Coupling of Advanced Guidance and Robust Control for the Descent and Precise Landing of Reusable Launchers.

Author

De Oliveira, Alice and Lavagna, Michèle

Subjects
FLIGHT control systems, COST functions, CLOSED loop systems, LAUNCH vehicles (Astronautics), ROBUST control, LANDING (Aeronautics)
Abstract

This paper investigates the coupling of successive convex optimization guidance with robust structured H ∞ control for the descent and precise landing of Reusable Launch Vehicles (RLVs). More particularly, this Guidance and Control (G&C) system is foreseen to be integrated into a nonlinear six-degree-of-freedom RLV controlled dynamics simulator which covers the aerodynamic and powered descent phase until vertical landing of a first-stage rocket equipped with a thrust vector control system and steerable planar fins. A cost function strategy analysis is performed to find out the most efficient one to be implemented in closed-loop with the robust control system and the vehicle flight mechanics involved. In addition, the controller synthesis via structured H ∞ is thoroughly described. The latter are built at different points of the descent trajectory using Proportional-Integral-Derivative (PID)-like structures with feedback on the attitude angles, rates, and lateral body velocities. The architecture is verified through linear analyses as well as nonlinear cases with the aforementioned simulator, and the G&C approach is validated by comparing the performance and robustness with a baseline system in nominal conditions as well as in the presence of perturbations. The overall results show that the proposed G&C system represents a relevant candidate for realistic descent flight and precise landing phase for reusable launchers. [ABSTRACT FROM AUTHOR]

Published
2024
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34. Cross-Spectral Navigation with Sensor Handover for Enhanced Proximity Operations with Uncooperative Space Objects.

Author

Bussolino, Massimiliano, Civardi, Gaia Letizia, Quirino, Matteo, Bechini, Michele, and Lavagna, Michèle

Subjects
INFRARED imaging, THERMOGRAPHY, MULTISPECTRAL imaging, KALMAN filtering, MULTISENSOR data fusion
Abstract

Close-proximity operations play a crucial role in emerging mission concepts, such as Active Debris Removal or small celestial bodies exploration. When approaching a non-cooperative target, the increased risk of collisions and reduced reliance on ground intervention necessitate autonomous on-board relative pose (position and attitude) estimation. Although navigation strategies relying on monocular cameras which operate in the visible (VIS) spectrum have been extensively studied and tested in flight for navigation applications, their accuracy is heavily related to the target's illumination conditions, thus limiting their applicability range. The novelty of the paper is the introduction of a thermal-infrared (TIR) camera to complement the VIS one to mitigate the aforementioned issues. The primary goal of this work is to evaluate the enhancement in navigation accuracy and robustness by performing VIS-TIR data fusion within an Extended Kalman Filter (EKF) and to assess the performance of such navigation strategy in challenging illumination scenarios. The proposed navigation architecture is tightly coupled, leveraging correspondences between a known uncooperative target and feature points extracted from multispectral images. Furthermore, handover from one camera to the other is introduced to enable seamlessly operations across both spectra while prioritizing the most significant measurement sources. The pipeline is tested on Tango spacecraft synthetically generated VIS and TIR images. A performance assessment is carried out through numerical simulations considering different illumination conditions. Our results demonstrate that a combined VIS-TIR navigation strategy effectively enhances operational robustness and flexibility compared to traditional VIS-only navigation chains. [ABSTRACT FROM AUTHOR]

Published
2024
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39. The Dimorphos ejecta plume properties revealed by LICIACube

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Dotto, Elisabetta, Deshapriya, J. D. Prasanna, Gai, Igor, Hasselmann, Pedro H., Mazzotta Epifani, Elena, Poggiali, Giovanni, Rossi, Alessandro, Zanotti, Giovanni, Zinzi, Angelo, Bertini, Ivano, Brucato, John Robert, Dall’Ora, Massimo, Della Corte, Vincenzo, Ivanovski, Stavro, Lucchetti, Alice, Pajola, Maurizio, Amoroso, Marilena, Barnouin, Olivier, Campo Bagatin, Adriano, Capannolo, Andrea, Caporali, S., Ceresoli, M., Chabot, Nancy, Cheng, Andy F., Cremonese, Gabriele, Fahnestock, Eugene G., Farnham, Tony, Ferrari, Fabio, Gomez Casajus, L., Gramigna, E., Hirabayashi, Masatoshi, Ieva, Simone, Impresario, Gabriele, Jutzi, Martin, Lasagni Manghi, R., Lavagna, Michèle, Li, Jian-Yang, Lombardo, M., Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Raducan, Sabina D., Richardson, Derek C., Rivkin, Andy, Stickle, Angela M., Sunshine, Jessica M., Tortora, Paolo, Tusberti, Filippo, Zannoni, Marco, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Dotto, Elisabetta, Deshapriya, J. D. Prasanna, Gai, Igor, Hasselmann, Pedro H., Mazzotta Epifani, Elena, Poggiali, Giovanni, Rossi, Alessandro, Zanotti, Giovanni, Zinzi, Angelo, Bertini, Ivano, Brucato, John Robert, Dall’Ora, Massimo, Della Corte, Vincenzo, Ivanovski, Stavro, Lucchetti, Alice, Pajola, Maurizio, Amoroso, Marilena, Barnouin, Olivier, Campo Bagatin, Adriano, Capannolo, Andrea, Caporali, S., Ceresoli, M., Chabot, Nancy, Cheng, Andy F., Cremonese, Gabriele, Fahnestock, Eugene G., Farnham, Tony, Ferrari, Fabio, Gomez Casajus, L., Gramigna, E., Hirabayashi, Masatoshi, Ieva, Simone, Impresario, Gabriele, Jutzi, Martin, Lasagni Manghi, R., Lavagna, Michèle, Li, Jian-Yang, Lombardo, M., Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Raducan, Sabina D., Richardson, Derek C., Rivkin, Andy, Stickle, Angela M., Sunshine, Jessica M., Tortora, Paolo, Tusberti, Filippo, and Zannoni, Marco

Abstract

The Double Asteroid Redirection Test (DART) had an impact with Dimorphos (a satellite of the asteroid Didymos) on 26 September 20221. Ground-based observations showed that the Didymos system brightened by a factor of 8.3 after the impact because of ejecta, returning to the pre-impact brightness 23.7 days afterwards2. Hubble Space Telescope observations made from 15 minutes after impact to 18.5 days after, with a spatial resolution of 2.1 kilometres per pixel, showed a complex evolution of the ejecta3, consistent with other asteroid impact events. The momentum enhancement factor, determined using the measured binary period change4, ranges between 2.2 and 4.9, depending on the assumptions about the mass and density of Dimorphos5. Here we report observations from the LUKE and LEIA instruments on the LICIACube cube satellite, which was deployed 15 days in advance of the impact of DART. Data were taken from 71 seconds before the impact until 320 seconds afterwards. The ejecta plume was a cone with an aperture angle of 140 ± 4 degrees. The inner region of the plume was blue, becoming redder with increasing distance from Dimorphos. The ejecta plume exhibited a complex and inhomogeneous structure, characterized by filaments, dust grains and single or clustered boulders. The ejecta velocities ranged from a few tens of metres per second to about 500 metres per second.

Published
2024

40. Fast boulder fracturing by thermal fatigue detected on stony asteroids

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Lucchetti, Alice, Cambioni, Saverio, Nakano, Ryota, Barnouin, Olivier, Pajola, Maurizio, Penasa, L., Tusberti, Filippo, Ramesh, K. T., Dotto, Elisabetta, Ernst, Carolyn, Daly, R. Terik, Mazzotta Epifani, Elena, Hirabayashi, Masatoshi, Parro, Laura M., Poggiali, Giovanni, Campo Bagatin, Adriano, Ballouz, Ronald-Louis, Chabot, Nancy, Michel, Patrick, Murdoch, Naomi, Vincent, Jean-Baptiste, Karatekin, Ozgür, Rivkin, Andy, Sunshine, Jessica M., Kohout, Tomas, Deshapriya, J. D. Prasanna, Hasselmann, Pedro H., Ieva, Simone, Beccarelli, Joel, Ivanovski, Stavro, Rossi, Alessandro, Ferrari, Fabio, Rossi, C., Raducan, Sabina D., Steckloff, Jordan, Schwartz, Stephen R., Brucato, John Robert, Dall’Ora, Massimo, Zinzi, Angelo, Cheng, Andy F., Amoroso, Marilena, Bertini, Ivano, Capannolo, Andrea, Caporali, S., Ceresoli, M., Cremonese, Gabriele, Della Corte, Vincenzo, Gai, Igor, Gomez Casajus, L., Gramigna, E., Impresario, Gabriele, Lasagni Manghi, R., Lavagna, Michèle, Lombardo, M., Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Tortora, Paolo, Zannoni, Marco, Zanotti, Giovanni, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Lucchetti, Alice, Cambioni, Saverio, Nakano, Ryota, Barnouin, Olivier, Pajola, Maurizio, Penasa, L., Tusberti, Filippo, Ramesh, K. T., Dotto, Elisabetta, Ernst, Carolyn, Daly, R. Terik, Mazzotta Epifani, Elena, Hirabayashi, Masatoshi, Parro, Laura M., Poggiali, Giovanni, Campo Bagatin, Adriano, Ballouz, Ronald-Louis, Chabot, Nancy, Michel, Patrick, Murdoch, Naomi, Vincent, Jean-Baptiste, Karatekin, Ozgür, Rivkin, Andy, Sunshine, Jessica M., Kohout, Tomas, Deshapriya, J. D. Prasanna, Hasselmann, Pedro H., Ieva, Simone, Beccarelli, Joel, Ivanovski, Stavro, Rossi, Alessandro, Ferrari, Fabio, Rossi, C., Raducan, Sabina D., Steckloff, Jordan, Schwartz, Stephen R., Brucato, John Robert, Dall’Ora, Massimo, Zinzi, Angelo, Cheng, Andy F., Amoroso, Marilena, Bertini, Ivano, Capannolo, Andrea, Caporali, S., Ceresoli, M., Cremonese, Gabriele, Della Corte, Vincenzo, Gai, Igor, Gomez Casajus, L., Gramigna, E., Impresario, Gabriele, Lasagni Manghi, R., Lavagna, Michèle, Lombardo, M., Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Tortora, Paolo, Zannoni, Marco, and Zanotti, Giovanni

Abstract

Spacecraft observations revealed that rocks on carbonaceous asteroids, which constitute the most numerous class by composition, can develop millimeter-to-meter-scale fractures due to thermal stresses. However, signatures of this process on the second-most populous group of asteroids, the S-complex, have been poorly constrained. Here, we report observations of boulders’ fractures on Dimorphos, which is the moonlet of the S-complex asteroid (65803) Didymos, the target of NASA’s Double Asteroid Redirection Test (DART) planetary defense mission. We show that the size-frequency distribution and orientation of the mapped fractures are consistent with formation through thermal fatigue. The fractures’ preferential orientation supports that these have originated in situ on Dimorphos boulders and not on Didymos boulders later transferred to Dimorphos. Based on our model of the fracture propagation, we propose that thermal fatigue on rocks exposed on the surface of S-type asteroids can form shallow, horizontally propagating fractures in much shorter timescales (100 kyr) than in the direction normal to the boulder surface (order of Myrs). The presence of boulder fields affected by thermal fracturing on near-Earth asteroid surfaces may contribute to an enhancement in the ejected mass and momentum from kinetic impactors when deflecting asteroids.

Published
2024

41. Evidence for multi-fragmentation and mass shedding of boulders on rubble-pile binary asteroid system (65803) Didymos

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Pajola, Maurizio, Tusberti, Filippo, Lucchetti, Alice, Barnouin, Olivier, Cambioni, Saverio, Ernst, Carolyn, Dotto, Elisabetta, Daly, R. Terik, Poggiali, Giovanni, Hirabayashi, Masatoshi, Nakano, Ryota, Mazzotta Epifani, Elena, Chabot, Nancy, Della Corte, Vincenzo, Rivkin, Andy, Agrusa, Harrison F., Zhang, Yun, Penasa, L., Ballouz, Ronald-Louis, Ivanovski, Stavro, Murdoch, Naomi, Rossi, Alessandro, Robin, Colas Q., Ieva, Simone, Vincent, Jean-Baptiste, Ferrari, Fabio, Raducan, Sabina D., Campo Bagatin, Adriano, Parro, Laura M., Benavídez, Paula Gabriela, Tancredi, Gonzalo, Karatekin, Ozgür, Trigo-Rodríguez, Josep M., Sunshine, Jessica M., Farnham, Tony, Asphaug, Erik, Deshapriya, J. D. Prasanna, Hasselmann, Pedro H., Beccarelli, Joel, Schwartz, Stephen R., Abell, Paul, Michel, Patrick, Cheng, Andy F., Brucato, John Robert, Zinzi, Angelo, Amoroso, Marilena, Pirrotta, Simone, Impresario, Gabriele, Bertini, Ivano, Capannolo, Andrea, Caporali, S., Ceresoli, M., Cremonese, Gabriele, Dall’Ora, Massimo, Gai, Igor, Gomez Casajus, L., Gramigna, E., Lasagni Manghi, R., Lavagna, Michèle, Lombardo, M., Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Tortora, Paolo, Zannoni, Marco, Zanotti, Giovanni, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Pajola, Maurizio, Tusberti, Filippo, Lucchetti, Alice, Barnouin, Olivier, Cambioni, Saverio, Ernst, Carolyn, Dotto, Elisabetta, Daly, R. Terik, Poggiali, Giovanni, Hirabayashi, Masatoshi, Nakano, Ryota, Mazzotta Epifani, Elena, Chabot, Nancy, Della Corte, Vincenzo, Rivkin, Andy, Agrusa, Harrison F., Zhang, Yun, Penasa, L., Ballouz, Ronald-Louis, Ivanovski, Stavro, Murdoch, Naomi, Rossi, Alessandro, Robin, Colas Q., Ieva, Simone, Vincent, Jean-Baptiste, Ferrari, Fabio, Raducan, Sabina D., Campo Bagatin, Adriano, Parro, Laura M., Benavídez, Paula Gabriela, Tancredi, Gonzalo, Karatekin, Ozgür, Trigo-Rodríguez, Josep M., Sunshine, Jessica M., Farnham, Tony, Asphaug, Erik, Deshapriya, J. D. Prasanna, Hasselmann, Pedro H., Beccarelli, Joel, Schwartz, Stephen R., Abell, Paul, Michel, Patrick, Cheng, Andy F., Brucato, John Robert, Zinzi, Angelo, Amoroso, Marilena, Pirrotta, Simone, Impresario, Gabriele, Bertini, Ivano, Capannolo, Andrea, Caporali, S., Ceresoli, M., Cremonese, Gabriele, Dall’Ora, Massimo, Gai, Igor, Gomez Casajus, L., Gramigna, E., Lasagni Manghi, R., Lavagna, Michèle, Lombardo, M., Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Tortora, Paolo, Zannoni, Marco, and Zanotti, Giovanni

Abstract

Asteroids smaller than 10 km are thought to be rubble piles formed from the reaccumulation of fragments produced in the catastrophic disruption of parent bodies. Ground-based observations reveal that some of these asteroids are today binary systems, in which a smaller secondary orbits a larger primary asteroid. However, how these asteroids became binary systems remains unclear. Here, we report the analysis of boulders on the surface of the stony asteroid (65803) Didymos and its moonlet, Dimorphos, from data collected by the NASA DART mission. The size-frequency distribution of boulders larger than 5 m on Dimorphos and larger than 22.8 m on Didymos confirms that both asteroids are piles of fragments produced in the catastrophic disruption of their progenitors. Dimorphos boulders smaller than 5 m have size best-fit by a Weibull distribution, which we attribute to a multi-phase fragmentation process either occurring during coalescence or during surface evolution. The density per km2 of Dimorphos boulders ≥1 m is 2.3x with respect to the one obtained for (101955) Bennu, while it is 3.0x with respect to (162173) Ryugu. Such values increase once Dimorphos boulders ≥5 m are compared with Bennu (3.5x), Ryugu (3.9x) and (25143) Itokawa (5.1x). This is of interest in the context of asteroid studies because it means that contrarily to the single bodies visited so far, binary systems might be affected by subsequential fragmentation processes that largely increase their block density per km2. Direct comparison between the surface distribution and shapes of the boulders on Didymos and Dimorphos suggest that the latter inherited its material from the former. This finding supports the hypothesis that some asteroid binary systems form through the spin up and mass shedding of a fraction of the primary asteroid.

Published
2024

42. The geology and evolution of the Near-Earth binary asteroid system (65803) Didymos

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Barnouin, Olivier, Ballouz, Ronald-Louis, Marchi, Simone, Vincent, Jean-Baptiste, Agrusa, Harrison F., Zhang, Yun, Ernst, Carolyn, Pajola, Maurizio, Tusberti, Filippo, Lucchetti, Alice, Daly, R. Terik, Palmer, Eric E., Walsh, Kevin J., Michel, Patrick, Sunshine, Jessica M., Rizos, Juan L., Farnham, Tony, Richardson, Derek C., Parro, Laura M., Murdoch, Naomi, Robin, Colas Q., Hirabayashi, Masatoshi, Kahout, Tomas, Asphaug, Erik, Raducan, Sabina D., Jutzi, Martin, Ferrari, Fabio, Hasselmann, Pedro H., Campo Bagatin, Adriano, Chabot, Nancy, Li, Jian-Yang, Cheng, Andy F., Nolan, Michael C., Stickle, Angela M., Karatekin, Ozgür, Dotto, Elisabetta, Della Corte, Vincenzo, Mazzotta Epifani, Elena, Rossi, Alessandro, Gai, Igor, Deshapriya, J. D. Prasanna, Bertini, Ivano, Zinzi, Angelo, Trigo-Rodríguez, Josep M., Beccarelli, Joel, Ivanovski, Stavro, Brucato, John Robert, Poggiali, Giovanni, Zanotti, Giovanni, Amoroso, Marilena, Capannolo, Andrea, Cremonese, Gabriele, Dall’Ora, Massimo, Ieva, Simone, Impresario, Gabriele, Lavagna, Michèle, Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Tortora, Paolo, Zannoni, Marco, Rivkin, Andy, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Barnouin, Olivier, Ballouz, Ronald-Louis, Marchi, Simone, Vincent, Jean-Baptiste, Agrusa, Harrison F., Zhang, Yun, Ernst, Carolyn, Pajola, Maurizio, Tusberti, Filippo, Lucchetti, Alice, Daly, R. Terik, Palmer, Eric E., Walsh, Kevin J., Michel, Patrick, Sunshine, Jessica M., Rizos, Juan L., Farnham, Tony, Richardson, Derek C., Parro, Laura M., Murdoch, Naomi, Robin, Colas Q., Hirabayashi, Masatoshi, Kahout, Tomas, Asphaug, Erik, Raducan, Sabina D., Jutzi, Martin, Ferrari, Fabio, Hasselmann, Pedro H., Campo Bagatin, Adriano, Chabot, Nancy, Li, Jian-Yang, Cheng, Andy F., Nolan, Michael C., Stickle, Angela M., Karatekin, Ozgür, Dotto, Elisabetta, Della Corte, Vincenzo, Mazzotta Epifani, Elena, Rossi, Alessandro, Gai, Igor, Deshapriya, J. D. Prasanna, Bertini, Ivano, Zinzi, Angelo, Trigo-Rodríguez, Josep M., Beccarelli, Joel, Ivanovski, Stavro, Brucato, John Robert, Poggiali, Giovanni, Zanotti, Giovanni, Amoroso, Marilena, Capannolo, Andrea, Cremonese, Gabriele, Dall’Ora, Massimo, Ieva, Simone, Impresario, Gabriele, Lavagna, Michèle, Modenini, Dario, Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Tortora, Paolo, Zannoni, Marco, and Rivkin, Andy

Abstract

Images collected during NASA’s Double Asteroid Redirection Test (DART) mission provide the first resolved views of the Didymos binary asteroid system. These images reveal that the primary asteroid, Didymos, is flattened and has plausible undulations along its equatorial perimeter. At high elevations, its surface is rough and contains large boulders and craters; at low elevations its surface is smooth and possesses fewer large boulders and craters. Didymos’ moon, Dimorphos, possesses an intimate mixture of boulders, several asteroid-wide lineaments, and a handful of craters. The surfaces of both asteroids include boulders that are large relative to their host body, suggesting that both asteroids are rubble piles. Based on these observations, our models indicate that Didymos has a surface cohesion ≤ 1 Pa and an interior cohesion of ∼10 Pa, while Dimorphos has a surface cohesion of <0.9 Pa. Crater size-frequency analyzes indicate the surface age of Didymos is 40–130 times older than Dimorphos, with likely absolute ages of ∼ 12.5 Myr and <0.3 Myr, respectively. Solar radiation could have increased Didymos’ spin rate leading to internal deformation and surface mass shedding, which likely created Dimorphos.

Published
2024

43. VADER: Probing the Dark Side of Dimorphos with LICIACube LUKE

Author

Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Zinzi, Angelo, Hasselmann, Pedro H., Della Corte, Vincenzo, Deshapriya, J. D. Prasanna, Gai, Igor, Lucchetti, Alice, Pajola, Maurizio, Rossi, Alessandro, Dotto, Elisabetta, Mazzotta Epifani, Elena, Daly, R. Terik, Hirabayashi, Masatoshi, Farnham, Tony, Ernst, Carolyn, Ivanovski, Stavro, Li, Jian-Yang, Parro, Laura M., Amoroso, Marilena, Beccarelli, Joel, Bertini, Ivano, Brucato, John Robert, Capannolo, Andrea, Caporali, S., Ceresoli, M., Cremonese, Gabriele, Dall’Ora, Massimo, Gomez Casajus, L., Gramigna, E., Ieva, Simone, Impresario, Gabriele, Lasagni Manghi, R., Lavagna, Michèle, Lombardo, M., Modenini, Dario, Negri, B., Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Poggiali, Giovanni, Tortora, Paolo, Tusberti, Filippo, Zannoni, Marco, Zanotti, Giovanni, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Zinzi, Angelo, Hasselmann, Pedro H., Della Corte, Vincenzo, Deshapriya, J. D. Prasanna, Gai, Igor, Lucchetti, Alice, Pajola, Maurizio, Rossi, Alessandro, Dotto, Elisabetta, Mazzotta Epifani, Elena, Daly, R. Terik, Hirabayashi, Masatoshi, Farnham, Tony, Ernst, Carolyn, Ivanovski, Stavro, Li, Jian-Yang, Parro, Laura M., Amoroso, Marilena, Beccarelli, Joel, Bertini, Ivano, Brucato, John Robert, Capannolo, Andrea, Caporali, S., Ceresoli, M., Cremonese, Gabriele, Dall’Ora, Massimo, Gomez Casajus, L., Gramigna, E., Ieva, Simone, Impresario, Gabriele, Lasagni Manghi, R., Lavagna, Michèle, Lombardo, M., Modenini, Dario, Negri, B., Palumbo, Pasquale, Perna, Davide, Pirrotta, Simone, Poggiali, Giovanni, Tortora, Paolo, Tusberti, Filippo, Zannoni, Marco, and Zanotti, Giovanni

Abstract

The ASI cubesat LICIACube has been part of the first planetary defense mission DART, having among its scopes to complement the DRACO images to better constrain the Dimorphos shape. LICIACube had two different cameras, LEIA and LUKE, and to accomplish its goal, it exploited the unique possibility of acquiring images of the Dimorphos hemisphere not seen by DART from a vantage point of view, in both time and space. This work is indeed aimed at constraining the tridimensional shape of Dimorphos, starting from both LUKE images of the nonimpacted hemisphere of Dimorphos and the results obtained by DART looking at the impacted hemisphere. To this aim, we developed a semiautomatic Computer Vision algorithm, named VADER, able to identify objects of interest on the basis of physical characteristics, subsequently used as input to retrieve the shape of the ellipse projected in the LUKE images analyzed. Thanks to this shape, we then extracted information about the Dimorphos ellipsoid by applying a series of quantitative geometric considerations. Although the solution space coming from this analysis includes the triaxial ellipsoid found by using DART images, we cannot discard the possibility that Dimorphos has a more elongated shape, more similar to what is expected from previous theories and observations. The result of our work seems therefore to emphasize the unique value of the LICIACube mission and its images, making even clearer the need of having different points of view to accurately define the shape of an asteroid.

Published
2024

44. Aggregating Models for Anomaly Detection in Space Systems: Results from the FCTMAS Study

Author

Amigoni, Francesco, Ferrari Dacrema, Maurizio, Donati, Alessandro, Laroque, Christian, Lavagna, Michèle, Riva, Alessandro, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Strand, Marcus, editor, Dillmann, Rüdiger, editor, Menegatti, Emanuele, editor, and Ghidoni, Stefano, editor

Published
2019
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46. Redundant Space Manipulator Autonomous Guidance for In-Orbit Servicing via Deep Reinforcement Learning.

Author

D'Ambrosio, Matteo, Capra, Lorenzo, Brandonisio, Andrea, Silvestrini, Stefano, and Lavagna, Michèle

Subjects
DEEP reinforcement learning, REINFORCEMENT learning, SPACE robotics, ORBITS of artificial satellites, SPACE trajectories, SPACE debris
Abstract

The application of space robotic manipulators and heightened autonomy for In-Orbit Servicing (IOS) represents a paramount pursuit for leading space agencies, given the substantial threat posed by space debris to operational satellites and forthcoming space endeavors. This work presents a guidance algorithm based on Deep Reinforcement Learning (DRL) to solve for space manipulator path planning during the motion-synchronization phase with the mission target. The goal is the trajectory generation and control of a spacecraft equipped with a 7-Degrees of Freedom (7-DoF) robotic manipulator, such that its end effector remains stationary with respect to the target point of capture. The Proximal Policy Optimization (PPO) DRL algorithm is used to optimize the manipulator's guidance law, and the autonomous agent generates the desired joint rates of the robotic arm, which are then integrated and passed to a model-based feedback linearization controller. The agent is first trained to optimize its guidance policy and then tested extensively to validate the results against a simulated environment representing the motion synchronization scenario of an IOS mission. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
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