Space physics is the study of everything above the Earth’s atmosphere, where the ionosphere and magnetosphere reside, and from the sun to the edge of the solar system. Plasmas, gases of charged particles, make up over 99% of the solar system such as in the sun’s core and corona, the solar wind, interplanetary space, and the planetary magnetospheres, and so are a natural focus of the discipline. The ionosphere is a gas of charged particles created by the ionization of particles in the atmosphere from UV radiation from the sun. The magnetosphere is a region of space around the Earth containing the Earth’s magnetic field, which is created by currents flowing in the Earth’s outer liquid core, and extends to where it meets the interplanetary magnetic field created by the solar wind (the magnetopause). The solar wind is a flux of charged particles ejected from the solar corona. The magnetosphere contains the Van Allen radiation belts, typically two belts containing high-energy charged particles trapped from the solar wind and the ionosphere. The discovery of these radiation belts in the 1950’s by James Van Allen, a professor who spent his career at the University of Iowa, through Explorer I launched space physics as a discipline. The solar wind interacts with the Earth’s magnetic field, and disturbances can lead to geomagnetic storms that can affect communication and GPS satellites, spacecraft, the power grid, and other technology.
Space physics research at the University of Iowa is world renowned, and alumni of the program include scientists such as Donald Gurnett (also spent his career as a professor at UI), whose discoveries include solving how auroras are created and detecting the heliopause (the boundary between our solar system and outer space) with Voyager 1, and James Hansen, a pioneering climatologist and former director of NASA Goddard Institute for Space Studies. In all, researchers at UI have contributed to instrumentation on over one hundred rocket and spacecraft missions. Current researchers study such topics as the origin of Jupiter's magnetosphere and magnetic field, the solar wind interacting with Mars and moons, near-sun electron properties, charged particle dynamics in the Earth’s magnetosphere, physics of the auroras, physics of magnetic reconnection at the magnetopause, magnetosphere-ionosphere coupling, Alfven waves, and exploring interstellar space. UI researchers continue to build instrumentation that contribute to spacecraft missions, including current and recent missions such as TRACERS, Juno, Van Allen Probes, MMS, and TRICE-2.
Four advanced courses in the fundamentals of plasma physics and its application in space and astrophysical environments are offered regularly, as well as specialty courses offered periodically on numerical simulations of plasmas, spacecraft instrumentation for plasma measurements, and data analysis methods in plasma physics and space physics. A plasma physics seminar and a space physics and astrophysics seminar are each held weekly during the academic year.
Developed science instruments currently operating on 13 spacecraft
Developed instrumentation on over 70 spacecraft
The NASA-funded Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS), which will study the mysterious, powerful interactions between the magnetic fields of the sun and Earth. The mission, led by Craig Kletzing, professor and Donald A. and Marie B. Gurnett Chair in the Department of Physics and Astronomy, received $115 million, making it the single largest externally funded research project in institutional history.
The Juno mission is conducting an in-depth study of the giant planet Jupiter. Juno is the first mission to use a polar orbit to study Jupiter, allowing it to carry out the first exploration of the polar magnetosphere which hosts the solar system's brightest auroras. The solar-powered spacecraft launched on August 5, 2011, and entered into Jupiter orbit on July 4, 2016, where it is investigating the existence of an ice-rock core, determining the amount of global water and ammonia present in the atmosphere, studying convection and deep wind profiles in the atmosphere, investigating the origin of the Jovian magnetic field, and exploring the polar magnetosphere.
Juno's mission at Jupiter was recently extended, beginning in August 2021. The mission extension provides for Juno to continue orbiting Jupiter until late 2025.
The Voyager 1 and 2 spacecraft are exploring where nothing from Earth has flown before – interstellar space. The two spacecraft, launched in 1977 each carrying a University of Iowa designed and built Plasma Wave Instrument, began their journeys by exploring the outer planets of our solar system before entering interstellar space. Data from the Iowa instruments have enabled researchers to make discoveries, including the first observations of plasma waves and low-frequency radio emissions in the magnetospheres of Jupiter, Saturn, Uranus, and Neptune; confirming the presence of lightning in the atmospheres of Jupiter and Neptune; the first measurements of the electron density in the interstellar medium, and the first detection in interstellar space of shocks related to solar activity.
Both spacecraft continue to send scientific information about their surroundings through the Deep Space Network.