On March 14, 2016, Dr. Ashish Goel from the Space Environment and Satellite Systems Lab at Stanford University visited NAOC and gave a talk about his research which is related to studying how collisions by small particles affect artificial satellites orbiting Earth. Dr. Goel recently graduated with a Ph.D. from Stanford University and will soon start a postdoctoral research position at Caltech. He is also the first winner of the RAA Excellent Paper Award for his article about hemispherical asymmetry of solar activity which was published in 2009.
Dr. Goel started his talk by showing a video of the Chelyabinsk meteor that exploded over Russia in 2013, saying that the associated blast wave damaged approximately 7000 buildings and injured around 1500 people. This event demonstrated the destructive potential of meteors impacting Earth's atmosphere. He continued by displaying a graph showing how the sizes of meteors are related to how often they encounter Earth and said that since small dust-sized meteors are very common, they pose the greatest danger to artificial satellites.
He then introduced his own work which involves modeling what happens when these small particles impact the metallic surface of an artificial satellite. He explained that a burst of plasma is generated over approximately a microsecond and a strong electromagnetic pulse is produced which can damage the electronic components of a spacecraft. He also described experiments he has conducted at facilities which can shoot small particles at targets, simulating the effects of a satellite impact in space, and the associated measurements he acquired. The work Dr. Goal is pursuing with help make future satellites and spacecraft more resistant to damage from small meteor impacts.