Penetration depth for shallow impact cratering

Penetration depth scaling for impact into wet granular packings.

We present experimental measurements of penetration depths for the impact of spheres into wetted granular media. We observe that the penetration depth in the liquid saturated case scales with projectile density, size, and drop height in a fashion consistent with the scaling observed in the dry case, but with smaller penetrations. Neither viscous drag nor density effects can explain the enhancem...

The Deep Impact oblique impact cratering experiment

The Deep Impact probe collided with 9P Tempel 1 at an angle of about 30◦ from the horizontal. This impact angle produced an evolving ejecta flow field very similar to much smaller scale oblique-impact experiments in porous particulate targets in the laboratory. Similar features and phenomena include a decoupled vapor/dust plume at the earliest times, a pronounced downrange bias of the ejecta, a...

Continuous penetration depth

We present a new measure for computing continuous penetration depth between two intersecting rigid objects. We generate a set of samples in the configuration space, precompute an approximation of the contact space for two intersecting objects using binary classification techniques, and construct a bijective mapping between the spherical space and the precomputed contact space. For a given in-co...

Martian Impact Cratering and Martian Layered Sediments

Multiband model for penetration depth in MgB2

The results of first-principles calculations of the electronic structure and the electron-phonon interaction in MgB2 are used to study theoretically the temperature dependence and anisotropy of the magnetic-field penetration depth. The effects of impurity scattering are essential for a proper description of the experimental results. We compare our results with experimental data and we argue tha...