The surface sensitivity of rubble-pile asteroids during a distant planetary encounter: Influence of asteroid shape elongation

Kim, Yaeji; Hirabayashi, Masatoshi; Binzel, Richard P.; Brozović, M.; Scheeres, Daniel J.; Richardson, D. C.

doi:10.1016/j.icarus.2020.114205

Cited by 11 publications

(9 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, the upper surface layers are structurally weak and fail relatively easily, as denoted by their low cohesive strengths. Surface mass shedding may also be triggered by small-scale events, for example, micrometeoroid impacts, thermal fatigue (Granvik et al 2016), or tidal effects (Kim et al 2021) causing small boulders to roll over the surface and kick up mass as it migrates. For the micrometeoroid impact case, further discussions are given below.…”

Section: Discussionmentioning

confidence: 99%

Active Main-belt Asteroid (6478) Gault: Constraint on Its Cohesive Strength and the Fate of Ejected Particles in the Solar System

Nakano¹,

Kim²,

Hirabayashi³

2022

Planet. Sci. J.

Self Cite

View full text Add to dashboard Cite

Active asteroid (6478) Gault sheds mass independent of location along its orbit. Rotational instability is considered to induce the observed activities. If this is the case, because Gault’s breakup event has not been detected, surface failure is likely, implying that its surface materials are constantly ejected while its major body remains intact. Given this scenario, we first constrain Gault’s bulk cohesive strength. We then characterize heliocentric trajectories of ejected particles over thousands of years. The results show that Gault may be sensitive to structural failure at the current spin period (∼2.5 hr). Gault’s bulk density needs to be below 1.75 g cm−3 in order for particles on the equatorial surface to be shed owing to centrifugal forces. In this case, Gault requires cohesive strength of at least ∼200 Pa to maintain the structure at the center, whereas the surface strength needs to be less than ∼100 Pa to induce mass shedding. This suggests that Gault’s structure may consist of a weak surface layer atop a strong core. The trajectories of dust ejected from Gault depend on how efficiently they are accelerated by solar radiation pressure. Escaped particle clouds with sizes of < ∼100 μm could collide with Gault after ∼700–5300 yr with speeds of ∼0.2 km s−1. This implies a temporal increase in the impact flux and complex interactions between the ejected particles and their host body.

show abstract

Section: Discussionmentioning

confidence: 99%

Active Main-belt Asteroid (6478) Gault: Constraint on Its Cohesive Strength and the Fate of Ejected Particles in the Solar System

Nakano¹,

Kim²,

Hirabayashi³

2022

Planet. Sci. J.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Surface mass shedding may also be triggered by small-scale events. For example, micrometeoroid impacts, thermal fatigue (Granvik et al 2016), or tidal effects (Kim et al 2021) causing small boulders to roll over the surface and kick up mass as it migrates. For the micrometeoroid impact case, further discussions are given below.…”

Section: Discussionmentioning

confidence: 99%

Active Main-Belt Asteroid (6478) Gault -- Constraint on Its Cohesive Strength and the Fate of Ejected Particles in the Solar System

Nakano¹,

Kim²,

Hirabayashi³

2021

Preprint

Self Cite

View full text Add to dashboard Cite

Active asteroid (6478) Gault sheds mass independent of location along its orbit. Rotational instability is considered to induce the observed activities. If this is the case, because Gault's breakup event hasn't been detected, surface failure is likely, implying its surface materials are constantly ejected while its major body remains intact. Given this scenario, we first constrain Gault's bulk cohesive strength. We then characterize heliocentric trajectories of ejected particles over thousands of years. The results show that Gault may be sensitive to structural failure at the current spin period (∼ 2.5 hr). Gault's bulk density needs to be below 1.75 g cm -3 in order for particles on the equatorial surface to be shed due to centrifugal forces. In this case, Gault requires cohesive strength of at least ∼ 200 Pa to maintain the structure at the center, whereas the surface strength needs to be less than ∼ 100 Pa to induce mass shedding. This suggests that Gault's structure may consist of a weak surface layer atop a strong core. The trajectories of dust ejected from Gault depend on how efficiently they are accelerated by solar radiation pressure. Escaped particle clouds with sizes of <∼ 100µm could collide with Gault after ∼ 700 − 5, 300 years with speeds of ∼ 0.2 km/sec. This implies a temporal increase in the impact flux and complex interactions between the ejected particles and their host body.

show abstract

“…It created a ∼15 m class crater (Arakawa et al 2020), demonstrating that impacts could significantly contribute to form craters on rubble-piles and to move boulders across the surface. Additionally, close encounters with planets could also modify the overall shape of the body by the effect of tides (Richardson et al 1998, Kim et al 2021). These small and large-scale alterations in shape contribute to a stochastic change of the spin-axis evolution onto a new set of YORP curves.…”

Section: Stochastic Yorp Effectmentioning

confidence: 99%

Mercury and OrbFit packages for the numerical integration of planetary systems: implementation of the Yarkovsky and YORP effects

Fenucci,

Novaković

2022

Preprint

View full text Add to dashboard Cite

For studies of the long-term evolution of small Solar System objects, it is fundamental to add the Yarkovsky and Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effects in the dynamical model. Still, implementations of these effects in publicly available N -body codes is often lacking, or the effects are implemented using significantly simplified models. In this paper, we present an implementation of the coupled Yarkovsky/YORP effects in the mercury and orbfit N -body codes. Along with these two effects, we also included the effects of non-destructive collisions and rotationally induced breakups to model the asteroid spin state properly. Given the stochastic nature of many incorporated effects, the software is suitable for statistical dynamical studies. Here we explained the scientific aspect of the implementation, while technical details will be made freely available along with the source codes.

show abstract

The surface sensitivity of rubble-pile asteroids during a distant planetary encounter: Influence of asteroid shape elongation

Cited by 11 publications

References 49 publications

Active Main-belt Asteroid (6478) Gault: Constraint on Its Cohesive Strength and the Fate of Ejected Particles in the Solar System

Active Main-belt Asteroid (6478) Gault: Constraint on Its Cohesive Strength and the Fate of Ejected Particles in the Solar System

Active Main-Belt Asteroid (6478) Gault -- Constraint on Its Cohesive Strength and the Fate of Ejected Particles in the Solar System

Mercury and OrbFit packages for the numerical integration of planetary systems: implementation of the Yarkovsky and YORP effects

Contact Info

Product

Resources

About