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 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 […]
[carousel-of-post-images imagesize=medium visible=3 count=15 postid=1353] 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 […]
[youtubegallery] TdNy-n1-y5A PHhL16cJ8hw [/youtubegallery] 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 […]
[carousel-of-post-images imagesize=medium visible=3 count=15 postid=898] 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 […]
[carousel-of-post-images imagesize=medium visible=3 count=15 postid=811] 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 […]
[youtubegallery] Contours of SO2 surface frost fraction over Io’s surface from Galileo NIMS observations. SO2 frost is omnipresent over Io’s surface but is concentrated in large patches at mid-latitudes.|cC0AzpPKp9Q Snapshots of Io’s atmosphere at ~20 minute intervals starting ~2.5 hours prior to eclipse. Circumplanetary flow develops due to the day-to-night […]
[carousel-of-post-images imagesize=medium visible=3 count=15 postid=800] 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, […]
[carousel-of-post-images imagesize=medium visible=3 count=15 postid=789] 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 […]
[carousel-of-post-images imagesize=medium visible=3 count=15 postid=783] 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 […]