Los Alamos Instruments Launch Aboard NASA Probe to Explore Solar Dynamics

Scientists at the Los Alamos National Laboratory (LANL) have developed two advanced instruments now aboard the National Aeronautics and Space Administration (NASA) probe, the Interstellar Mapping and Acceleration Probe (IMAP). Launched in September 2023, this mission aims to deepen understanding of the sun and the heliosphere, a protective region enveloping the solar system that shields it from harmful cosmic rays.

The IMAP spacecraft is currently on its way to the first Lagrange point, a gravitationally stable location situated between the Earth and the sun. It will take approximately four months to reach this point, with full instrument operation expected to begin by mid-January 2024. This mission builds upon findings from NASA’s previous Interstellar Boundary Explorer (IBEX), which launched in 2008. LANL’s IMAP-Hi instrument promises enhanced capabilities to filter background noise, thereby addressing gaps in data collected by IBEX.

“IBEX was really a mission of discovery,” noted Herb Funsten, the instrument lead on IMAP-Hi. “We didn’t know what we were actually going to find, so the IBEX instrument was not very optimized, and we discovered things that were completely unpredicted.” This new mission seeks to refine those discoveries and provide a clearer understanding of the sun’s influence on the heliosphere.

The heliosphere acts as the first line of defense against galactic rays, which are highly charged particles that pose risks to human DNA, disrupt radio communications, and can damage satellites. The heliosheath, the outer boundary of the heliosphere, reduces the intensity of these rays by a factor of ten. While other stars also create similar protective bubbles, researchers focus on the sun to seek an invisible signature of its activity.

Understanding the solar wind—charged particles emitted by the sun—constitutes a significant aspect of the IMAP mission. The two instruments, IMAP-Hi and the Solar Wind Electron instrument, will work together to map the heliosphere’s composition and structure. IMAP-Hi will collect and track energetic neutral atoms, providing crucial data on particle origins. Meanwhile, the Solar Wind Electron instrument will monitor electrons from the solar wind, helping to define the size and shape of the heliosphere and its interaction with the interstellar medium.

“It’s like a bat using sonar to figure out the distance to the walls of the cave,” explained Dan Reisenfeld, a LANL scientist. “For the heliosphere, we use the solar wind as that pulse.” This method allows researchers to create a detailed map of the heliosphere’s boundaries.

The sun’s 11-year cycle introduces variability in the heliosphere’s protective capabilities. During certain periods, the heliosphere can expand or contract, exhibiting boundary fluctuations akin to “breathing.” Recently, the Solar Wind Electron instrument successfully tracked a significant solar storm that occurred around Veterans Day, leading to the visibility of the northern lights at unusually low latitudes, including locations like Santa Fe.

While the beauty of solar storms captivates observers, they also pose potential hazards. Solar storms can disrupt power systems and create risks for astronauts in space. “We’re going to do even better on the next storm, with all the instruments on,” said Ruth Skoug, LANL’s lead on the Solar Wind Electron instrument. Understanding these phenomena is crucial for mitigating their impacts and enhancing safety for both terrestrial and space operations.

As the IMAP mission progresses, the insights gained from these instruments may significantly enhance our understanding of solar dynamics and the broader cosmic environment, paving the way for future explorations into the complexities of our solar system.