The 1999 Impact of Lunar Prospector into the Lunar South Pole

Lunar Prospector impacted the moon back in 1999. This is a copy of the old web page from that time. Some of the old links no longer function, some do. Impact occurred at 09:52:02 GMT on July 31 1999 (5:52am Eastern Daylight Time, 02:52am Pacific Daylight Time)New – 12/2/99:The Learning […]

Hypersonic Forward-Facing Cavity Flow

Hypersonic vehicles travel at such high velocities that severe heating and shape changes due to ablation often occur. These shape changes need to be minimized as they can produce unacceptable perturbations in the aerodynamics and, therefore, the flight. The heat loads and material ablation that lead to the shape changes […]

Hybrid DSMC/CFD Study of Hypersonic Boundary Layer Flow Over Roughness

In 2009, a series of boundary layer transition experiments were designed and flown as part of the STS-119, STS-125 and STS-128 missions (Figure 1).  As part of these flight experiments, a discrete protuberance was integrated into the shuttle tile material, and this tile was affixed to the port side wing […]

Sensitivity Analysis and Calibration of DSMC Input Parameters

In this work, statistical techniques were employed to study the modeling of a hypersonic shock with the Direct Simulation Monte Carlo (DSMC) method, and to gain insight into how the model interacts with a set of physical parameters. Direct Simulation Monte Carlo (DSMC) is a particle based method which is […]

Simulating Comet Impacts on the Moon

Over the last four billion years, a large amount of cometary material is estimated to have impacted the Moon. Water ice is thought to be the major constituent of comet nuclei, and analysis of hydrogen isotopes present in lunar minerals suggests the possibility of a cometary source for lunar water. […]

Simulations of Turbulent Spots and Wedges over Textured Surfaces

Turbulent spots are arrowhead shaped pockets of turbulent that form in the late stages of laminar to turbulent transition process (red circle in the schematic below). These spots increase in size as they travel downstream and form fully turbulent flow as they merge together. My research is looking at the […]

Simulating the Atmosphere of Jupiter’s Moon Io

Io has one of the most dynamic atmospheres in the solar system due in part to an orbital resonance with Europa and Ganymede that causes intense tidal heating and volcanism. The volcanism serves to create a myriad of volcanic plumes across Io’s surface that sustain temporally varying local atmospheres. The […]

Modeling Volcanic Plumes on Jupiter’s Moon Io

Io is the most volcanically active body in the solar system, and its volcanic plumes rise hundreds of kilometers above the surface.  They rise far above the atmosphere, and I model this plume expansion into a near-vacuum with Direct Simulation Monte Carlo.  I simulate Pele, one of the largest plumes, […]

Modeling the Plumes on Saturn’s Moon Enceladus

The Cassini spacecraft first detected a plume near the warm south pole of the Saturnian moon Enceladus in 2005. The discovery of the plume not only helped to explain some phenomena that have been puzzling scientists for a long time but also brought about the exciting possibility of finding liquid […]

Simulation of Rocket Plume Impingement and Dust Dispersal on the Lunar Surface

When a rocket lands on the Moon the engine exhaust plume will strike the lunar surface and disturb and disperse dust and larger debris. For any pre-existing structures (or residents) that plume of particulate ejecta represents a significant safety hazard. The scattered particles may penetrate weak surfaces, get stuck in […]