Global-scale Reshaping and Resurfacing of Asteroids by Small-scale Impacts, with Applications to the DART and Hera Missions

Raducan, Sabina D.; Jutzi, Martin

doi:10.3847/psj/ac67a7

Cited by 36 publications

(35 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As rocks tend to be weaker with increasing size, it is possible that asteroids in the 1 km diameter range are already in the gravity-dominated regime (Asphaug et al 2002), as found with the SCI impact on Ryugu (Arakawa et al 2020). The DART impact on a cohesionless Dimorphos would be likely to produce morphologies that are dissimilar to simple cratering events and would change the global morphology of the asteroid (Raducan & Jutzi 2022).…”

Section: Impact Physicsmentioning

confidence: 99%

The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos

et al. 2022

Self Cite

View full text Add to dashboard Cite

Hera is a planetary defense mission under development in the Space Safety and Security Program of the European Space Agency for launch in 2024 October. It will rendezvous in late 2026 December with the binary asteroid (65803) Didymos and in particular its moon, Dimorphos, which will be impacted by NASA’s DART spacecraft on 2022 September 26 as the first asteroid deflection test. The main goals of Hera are the detailed characterization of the physical properties of Didymos and Dimorphos and of the crater made by the DART mission, as well as measurement of the momentum transfer efficiency resulting from DART’s impact. The data from the Hera spacecraft and its two CubeSats will also provide significant insights into asteroid science and the evolutionary history of our solar system. Hera will perform the first rendezvous with a binary asteroid and provide new measurements, such as radar sounding of an asteroid interior, which will allow models in planetary science to be tested. Hera will thus provide a crucial element in the global effort to avert future asteroid impacts at the same time as providing world-leading science.

show abstract

Section: Impact Physicsmentioning

confidence: 99%

The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…The corresponding orbital period change is ∼−200 s. This result indicates that even though Dimorphos's mass accounts for only ∼1% of the total system mass, if global deformation occurs, the mutual gravitational field is greatly modified, leading to a large orbital period change. Importantly, if Dimorphos experiences a global deformation, it implies that its structure is weak(Raducan & Jutzi 2022;Stickle et al 2022). Then, it is possible that the…”

mentioning

confidence: 99%

NASA’s Double Asteroid Redirection Test (DART): Mutual Orbital Period Change Due to Reshaping in the Near-Earth Binary Asteroid System (65803) Didymos

et al. 2022

Self Cite

View full text Add to dashboard Cite

The Double Asteroid Redirection Test (DART) is the first planetary defense mission to demonstrate the kinetic deflection technique. The DART spacecraft will collide with the asteroid Dimorphos, the smaller component of the binary asteroid system (65803) Didymos. The DART impact will excavate surface/subsurface materials of Dimorphos, leading to the formation of a crater and/or some magnitude of reshaping (i.e., shape change without significant mass loss). The ejecta may eventually hit Didymos’s surface. If the kinetic energy delivered to the surface is high enough, reshaping may also occur in Didymos, given its near-critical spin rate. Reshaping on either body will modify the mutual gravitational field, leading to a reshaping-induced orbital period change, in addition to the impact-induced orbital period change. If left unaccounted for, this could lead to an erroneous interpretation of the effect of the kinetic deflection technique. Here we report the results of full two-body problem simulations that explore how reshaping influences the mutual dynamics. In general, we find that the orbital period becomes shorter linearly with increasing reshaping magnitude. If Didymos’s shortest axis shrinks by ∼0.7 m, or Dimorphos’s intermediate axis shrinks by ∼2 m, the orbital period change would be comparable to the Earth-based observation accuracy, ∼7.3 s. Constraining the reshaping magnitude will decouple the reshaping- and impact-induced orbital period changes; Didymos’s reshaping may be constrained by observing its spin period change, while Dimorphos’s reshaping will likely be difficult to constrain but will be investigated by the ESA's Hera mission that will visit Didymos in late 2026.

show abstract

“…Raducan et al (2019) studied impacts on targets with cohesion between 0.1 and 100 kPa. However, due to the new evidence of very weak asteroid surfaces (e.g., Walsh et al 2019;Arakawa et al 2020), this study was extended by Raducan & Jutzi (2022) to impacts on targets with cohesion down to 0 Pa. They found that, when impacting a target with fixed, 40% porosity and f = 0.6, the β factor increases from ≈3.5 for a 50 Pa target to β ≈ 5 for a cohesionless 0 Pa target.…”

Section: Systematic Numerical Studies On the Influence Of Physicalmentioning

confidence: 94%

“…In Figure 1(a), the dotted lines show the total amount of ejecta mass that does not escape the Didymos system. As discussed in Raducan & Jutzi (2022), for impacts on strong targets (Y 0 > ≈50 Pa), most of the mass is ejected at speeds higher than the escape velocity of the Didymos system. The reason for this is that the ejected material must have a maximum speed that exceeds the escape velocity needed to overcome the cohesive strength of the target (Raducan et al 2019;Raducan & Jutzi 2022).…”

Section: Momentum Distribution In Ejectamentioning

confidence: 99%

“…In Figure 1(a), the solid lines show the total mass of ejecta, and in Figure 1(b), the solid lines show the momentum enhancement, β, from impact simulations using the Bern smoothed particle hydrodynamics (SPH) and iSALE-2D codes for targets with constant porosity (40%) and varying cohesion and coefficient of internal friction. For completeness, here we plot the results from both the Bern SPH study (Raducan & Jutzi 2022) and the iSALE-2D study (Raducan et al 2019). However, there are slight variations in terms of strength and porosity model parameters between the simulations in the two studies, and a direct comparison between the results should be avoided.…”

Section: Momentum Distribution In Ejectamentioning

confidence: 99%

See 1 more Smart Citation

Heliocentric Effects of the DART Mission on the (65803) Didymos Binary Asteroid System

Makadia¹,

Raducan²,

Fahnestock³

et al. 2022

Planet. Sci. J.

Self Cite

View full text Add to dashboard Cite

The Double Asteroid Redirect Test (DART) is NASA’s first kinetic impact–based asteroid deflection mission. The DART spacecraft will act as a projectile during a hypervelocity impact on Dimorphos, the secondary asteroid in the (65803) Didymos binary system, and alter its mutual orbital period. The initial momentum transfer between the DART spacecraft and Dimorphos is enhanced by the ejecta flung off the surface of Dimorphos. This exchange is characterized within the system by the momentum enhancement parameter, β, and on a heliocentric level by its counterpart, β ⊙. The relationship between β and the physical characteristics of Dimorphos is discussed here. A nominal set of Dimorphos physical parameters from the design reference asteroid and impact circumstances from the design reference mission are used to initialize the ejecta particles for dynamical propagation. The results of this propagation are translated into a gradual momentum transfer onto the Didymos system barycenter. A high-quality solar system propagator is then used to produce precise estimates of the post-DART encounters between Didymos and Earth by generating updated close approach maps. Results show that even for an unexpectedly high β ⊙, a collision between the Didymos system and Earth is practically excluded in the foreseeable future. A small but significant difference is found in modeling the overall momentum transfer when individual ejecta particles escape the Didymos system, as opposed to imparting the ejecta momentum as a single impulse at impact. This difference has implications for future asteroid deflection campaigns, especially when it is necessary to steer asteroids away from gravitational keyholes.

show abstract

Global-scale Reshaping and Resurfacing of Asteroids by Small-scale Impacts, with Applications to the DART and Hera Missions

Cited by 36 publications

References 52 publications

The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos

The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos

NASA’s Double Asteroid Redirection Test (DART): Mutual Orbital Period Change Due to Reshaping in the Near-Earth Binary Asteroid System (65803) Didymos

Heliocentric Effects of the DART Mission on the (65803) Didymos Binary Asteroid System

Contact Info

Product

Resources

About