Plasma and Space Physics Projects


ISINGLASS (Ionospheric Structuring: In Situ and Groundbased Low Altitude Studies)

The upcoming ISINGLASS sounding rocket mission (February 2017, Poker Flat Rocket Range, Alaska) will sample multiple locations simultaneously in the auroral ionosphere to take gradient measurements of plasma parameters. Two identical rockets will be flown into two separate events (ie, quiet early evening arc vs dynamic rayed arc); each rocket has a large subpayload, and four small deployable payloads.

Measuring Travelling Ionospheric Disturbances Using Transmitters of Opportunity

Travelling Ionospheric Disturbances (TIDs) result from  large-scale waves in the upper atmosphere somewhat analogous to ocean waves, though propagating internal to the medium rather than on the surface. By transporting energy  they play a role in determining the temperature profile of the upper atmosphere. They also affect radio signals propagating through and beneath the ionosphere. Dartmouth students are involved in operating radio receivers in at least four sites in the northeastern United States, detecting TIDs through the small (0.1 Hz) Doppler shift that their ionospheric motions impose on reflecting AM radio signals. A goal is to determine many properties of the TIDs, including propagation directions and waveform shapes, from observed Doppler shifts at multiple locations.


Computer simulations of stellar winds interacting with the interstellar medium

Space observatories are finding more and more stars that lose some of their atmosphere in the form of a stellar wind (like our Sun’s solar wind) which interacts with the ever-present interstellar gas in such a way that bow shocks and other interaction features light up. The project focuses on simulating this stellar wind / dense interstellar gas interaction in 3D, synthesizing observables numerically, and then comparing them to the observations to explore the physics of the interaction. The project involves computer modeling (adapting an existing solar wind model) and analyzing simulation data. The prerequisite is having an affinity for using computers extensively in this way.


Characterizing the out-of-ecliptic solar wind

The focus of this project is the solar wind, a steady plasma stream of solar atmosphere lost by the Sun and blowing past the planets. Spacecraft have measured the solar wind for many decades. All but one spacecraft observe in the ecliptic plane (Earth’s orbital plane). For studies of the global heliosphere (Voyager 1, 2; IBEX), the complete 3D solar wind is needed as input, including the out-of-ecliptic solar wind. The only mission to ever measure solar wind away from the equator was Ulysses, a NASA/ESA mission (1992-2009). The Ulysses solar wind data need to be analyzed, separating their long-term behavior from short-term fluctuations, and generalized in a statistical manner in order to characterize possible, realistic 3D configurations of the solar wind. The project is dominated by computer work. The prerequisite is having an affinity for using computers extensively in this way.


Plasma Turbulence

Professor Barrett Rogers's research in theoretical and computational plasma physics addresses problems in turbulence, a ubiquitous feature of plasma systems. It can arise, for example, from non-uniformities in plasma flows, or be driven by instabilities arising from non-uniformities in the plasma density or temperatures. In magnetic fusion experiments, small-scale instabilities generate turbulence at small scales, which in turn transport plasma and heat from the core of fusion reactors to the walls. The convective losses generated in this way are among the greatest difficulties facing the design of a feasible fusion device.


Magnetic Reconnection

Professor Barrett Rogers's research in theoretical and computational plasma physics addresses problems in magnetic reconnection. Space and laboratory plasmas such as the sun, the magnetosphere, and laboratory fusion experiments often store large quantities of energy in embedded magnetic fields. Magnetic reconnection is a ubiquitous process that can convert some fraction of this energy, often explosively, into high speed flows and thermal energy. Reconnection is the fundamental process underlying cataclysmic phenomena such as coronal mass ejections, magnetospheric substorms, and "sawtooth-crash'' reconnection in tokamak fusion reactors. The rapidity of such events is often so extreme that it has been an ongoing challenge to explain theoretically. Reconnection also generates intense electric fields that can accelerate particles to very high energies.


Evolution of the Earth's Van Allen Radiation Belts

The evolution of the Earth's Van Allen Radiation Belts is being modeled by following test particle trajectories in 2D and 3D simulations using 3D magnetohydrodynamic fields from the Lyon-Fedder-Mobarry MHD code driven by measured plasma parameters from spacecraft in the solar wind upstream from Earth. Global electric and magnetic field structure and computed particle distributions in momentum and spatial location are compared with measurements from the recently launched (August 30, 2012) Van Allen Probes satellites. This work is supported by the NASA Heliophysics Directorate. Separate work on the access, trapping and loss of solar energetic protons in Earth's 'magnetosphere' is funded by NSF.


Green Cube

The undergraduates in the JPL-sponsored GreenCube project of the Lynch Rocket Lab, are developing a CubeSat-class autonomous sensor payload, which they fly on balloons across New Hampshire and this spring will be floating in an array down the Connecticut (and other) River(s). ``Cubesat'' is a small satellite prototype established by CalPoly and Stanford Universities. Similar satellites have been used by many other universities and student satellite programs because of its relatively easy and inexpensive design. Our 3UCubeSat payloads fly on bursting balloons that reach approximately 90,000 ft. in the air before falling back to earth with a parachute. The total flight takes approximately two hours. We have flown 6 such flights across NH so far. This spring we will be floating an array of 20 Arduino-based GPS-enabled GreenCube payloads down rivers to study river transport of large woody debris, an important parameter in geography studies of fluvial morphology and of recent importance in Vermont given the damage done by Hurricane Irene last year.