I am interested in the formation of the solar corona and solar wind -- and the tools we use to probe them. The Sun's magnetic field links every aspect of the solar system, from the star's deep interior to the environment in deep space and planetary neighborhoods, to the dimensions of our local bubble in interstellar space.
This system (the "heliosphere") is large and complex, and each element of it has become the subject of an entire scientific specialty. We are on the cusp of a new era of integrated heliophysics, when the entire system can be understood and studied as more than the sum of its isolated parts.
I lead the Heliophysics section of , located in Boulder, Colorado.
I am the Principal Investigator for the , a . Planned for launch in 2023, PUNCH will provide wide-field 3D images of the entire inner solar system, to understand the corona and the solar wind as a unified system.
Southwest Research Institute
The Young Solar Wind: The solar wind that impacts Earth and our spacecraft beyond 1AU is quite different from the solar wind at the top of the solar corona. Understanding the state of this material as it leaves the Sun is critical to understanding the Earth-Sun system as a unified whole. This "young solar wind" has not been heavily processed by turbulence or stream interactions, and contains signatures of its origin in the low solar corona. Measurements remain sparse, but that is changing. is flying through this region and sampling it with in-situ instrumentatioon. will image the region directly.
Imaging Science: Scientific images are counterintuitive: they are both surprisingly powerful and surprisingly limited. Understanding the nuances of scientific imaging is critical because images are so essential to heliophysics -- but it's also fascinating in its own right. Imaging science is an aspect of data science -- a field too many practicing scientists neglect.
MHD modeling: Magnetic reconnection and its consequences are critical to understanding the solar corona. Magnetohydrodynamics is too complex to be addressed analytically in nontrivial cases, so everyone uses numerical simulation to understand it. Conventional numerical codes have specific, well-known limitations. We’ve been exploring a different approach to MHD modeling -- fluxon modeling -- that allows simulation of certain systems in the complete absence of unwanted magnetic reconnection with, with much less computing power. Current efforts focus on adapting the code for space weather prediction, an application that requires a balance between physical fidelity and computing feasibility.
Open Source Scientific Computing: I am a strong advocate of open source computing for science. For nearly 20 years, I’ve been a developer for the . In recent years, it has become increasingly clear that Scientific Python, in particular the , , and packages, has the traction to become a mainstream replacement to proprietary packages. We are moving toward adopting Python as the official analysis language for PUNCH.
Lowering barriers to space: Developing new instrumentation is difficult. Developing new instrumentation for spaceflight or near-space flight on balloons is made more difficult by the constraints of the vehicles. At most ground-based observatories, existing infrastructure (a telescope, observing system, and optical table) delivers a conditioned, steered beam of photons to a controlled place on an optical table in a controlled interior environment. This separates the problems of observatory infrastructure from the problem of instrument development. That stands in contrast to balloon gondolas or sounding rockets -- which require expensively engineered point designs. A medium-term project for us is developing an agile, groundlike observatory that can be deployed cheaply into near-space to reduce the cost of new instrumentation.