1,1,2- 1Institute of Physics Applied to Sciences and Technologies, University of Alicante, SPAIN
- 2Department of Physics, Systems Engineering and Signal Theory, University of Alicante, SPAIN
- 3Planetary Science Institute, Tucson, Arizona, USA
- 4Astronomical Observatory Institute, Adam Mickiewicz University, Poland
- 5Dipartimento di Fisica e Astronomia. Università degli Studi di Padova, Italy
The Double Asteroid Redirection Test (DART, NASA) mission and the Hera space mission (ESA) are part of the Asteroid Impact and Deflection Assessment (AIDA) international collaboration supported by NASA and ESA. The target is the near-Earth binary asteroid, (65803) Didymos, which consists of a 800-m wide S-type asteroid (Didymos) and a 160-m wide asteroid (Dimorphos).
Our group had developed two different models — INSIDE (INternal Structure realistIc moDElling) and AROUND (AsteROid accUrate calculatioN of gravitational fielD) — to generate the possible synthetic rubble-pile structures and to calculate the gravitational field of arbitrary mass distributions. We now plan to build a suitable pipeline to suit the model of internal structure of Didymos and Dimoprhos to the Hera mission data available at different mission phases, through the INSIDE and OUTSIDE models.
The interaction between the data flow and modeling tools will be implemented and tested before Hera reaches the Didymos system in late December 2026. Starting from January 2027, Hera mission will enter Early Characterization Phase (ECF), and estimate the mass and volume of Didymos. As entering Detailed Characterisation Phase (DCP), the space measurements, GRASS and JuRa, will operate and generate a more precise asteroid model with AROUND and INSIDE. After Close Observation Phase (COP), the monostatic radar measurement of JuRa will constrain the structure of Dimorphos. At the end, in the Experimental Phase (EP), the instrumentation will orbit at low altitude and provide accurate radar and gravity measurements, and optimize the Didymos binary interior model.
In the project, we aim to design a pipeline for inspecting asteroid interiors through combining the spacecraft data to optimize modeling of gravity and internal structure from Hera mission within measurement uncertainty limits. Such internal structure modelling will be applied to later missions, such as the RAMSES mission (ESA) to asteroid Apophis in 2029.
How to cite: Chang, T.-H., Campo Bagatin, A., Liu, P.-Y., Pérez Molina, M., Schwartz, S., Bartczak, P., and Benavidez, P.: Asteroid internal structure determination from Hera mission, EPSC-DPS Joint Meeting 2025, Helsinki, Finland, 7–12 Sep 2025, EPSC-DPS2025-1359, https://doi.org/10.5194/epsc-dps2025-1359, 2025.
