Impakty, které poslaly meteoroidy k Zemi

• Název práce v češtině: Impakty, které poslaly meteoroidy k Zemi
• Název v anglickém jazyce: The impacts that send meteoroids to Earth
• Klíčová slova: impakt|meteoroidy
• Klíčová slova anglicky: impact|meteoroids
• Akademický rok vypsání: 2023/2024
• Typ práce: diplomová práce
• Ústav: Astronomický ústav UK (32-AUUK)
• Vedoucí / školitel: doc. Mgr. Miroslav Brož, Ph.D.

Zásady pro vypracování

According to observations and radiometric signatures, around 470\, My ago,
our planet witnessed a massive infall of L-chondrite meteoriods.
The only plausible source of these meteoroids is a collision
that created the asteroid family related to (20) Massalia.
Observations also show that 40\,My ago,
Massalia suffered another collision and formed a second family.
Material from the more recent event makes almost 40\% of meteorite falls today
(Marsset et al. submit., Brož et al. submit.).

Our goal is to create a model for the respective collisions,
using the smooth particle hydrodynamics (SPH) method.
The computation should include a number physical processes, in particular,
the impact itself, compression, decompression, deformation, vaporisation,
shock wave, rarefaction wave, expansion, ejection, self-gravity,
reaccumulation, merging, binary formation. We plan to use a state-of-the-art code,
Opensph (Ševeček et al. 2021).

The model will be constrained by the observed size-frequency distribution (SFD),
the size, shape, and the current rotation state of (20) Massalia.
In the near future, also the rotational states of small family members will be available (Ďurech & Hanuš 2023).
At the same time, it is necessary to account for the abundance of dust
produced by the 2nd impact, which is observed as the 1.4-deg dust band by IRAS (Nesvorný et al. 2006).
This requires an extrapolation of the SFD to 100-$\mu$ sizes.
The results will be also discussed in context of adaptive-optics observations
by the VLT/SPHERE instrument, planned for late 2024.

Seznam odborné literatury

Brož, M. et al., Young asteroid families as the primary source of meteorites.
Nature submit., https://arxiv.org/pdf/2403.08552.

Ďurech, J., Hanuš, J., Reconstruction of asteroid spin states from Gaia DR3 photometry.
Astron. Astrophys. 657, A24, 2023.

Nesvorný, D. et al., Physical properties of asteroid dust bands and their sources.
Icarus 181, 107, 2006.

Marsset, M. et al., The Massalia asteroid family as the origin of ordinary L chondrites.
Nature, submit., https://arxiv.org/abs/2403.08548.

Ševeček, P., Simulations of asteroid collisions using a hybrid SPH/N-body approach.
PhD Thesis, Charles Univ., 2021.

Ševeček, P. et al., Impacts into rotating targets: angular momentum draining and
efficient formation of synthetic families. Astron. Astrophys. 629, A122, 2019.