Can smartphones detect geomagnetic storms?

A recent study by S. F. Odenwald from NASA/GSFC has shown that smartphone magnetometers can detect geomagnetic storms:

“Smartphone magnetometers are being commercially explored for applications as diverse as locating customers in shopping malls for targeted advertising, to precision needle-guided surgery. Meanwhile, Earth’s geomagnetic field, whose measurement forms the basis for precision positing monitoring, varies on many timescales with significant amplitudes. This presents a challenge for high-precision position sensing that demands stability in the local geomagnetic field at the microTesla-level over timescales of minutes to hours. This study shows that many smartphone models have the sensitivity to detect geomagnetic storms caused by space weather, which means that under certain circumstances, geomagnetic storms could be a significant source of error in compass and other positioning applications. ” [Odenwald 2022]

Figure: Artist’s rendition of Earth’s magnetosphere [Credit: NASA]

Eugene Parker (1927-2022), a solar physics legend

Prof. Eugene N. Parker, a solar physics legend who first proposed the concept of the solar wind and is thus a namesake of the Parker Solar Probe mission passed away on 15 March at the age of 94. His great contributions to the field of solar physics were summarized in the obituary published by the University of Chicago:

“Parker was internationally known for proposing the concept of the solar wind—an idea that was first met with skepticism to outright ridicule. The theory was later proven to be correct, reshaping our picture of space and the solar system. Parker went on to revolutionize the field of astrophysics, unraveling the complex physics behind magnetic fields in space and the dynamics of plasma. In August 2018, at the age of 91, he became the first person to witness the launch of their namesake spacecraft.

Born in 1927 in Houghton, Michigan, Parker completed his undergraduate degree in physics from Michigan State University in 1948 and his Ph.D. from Caltech in 1951. He spent time as an instructor and assistant professor at the University of Utah before accepting a position in 1955 at the University of Chicago, where he remained for the rest of his career.

In 1957, Parker was a young assistant professor when he turned his attention to the temperature of the corona of the sun. Running through the math, he determined the conditions should produce a supersonic flow of particles off the sun’s surface. The idea was roundly criticized. “The first reviewer on the paper said, ‘Well I would suggest that Parker go to the library and read up on the subject before he tries to write a paper about it, because this is utter nonsense,’” Parker told UChicago News in 2018. The paper might not have been published but for Parker’s colleague at the University, Subrahmanyan Chandrasekhar. The editor of the journal and a future Nobel laureate, Chandrasekhar didn’t like the idea either—but he couldn’t find a flaw with Parker’s math, so he overrode the reviewers and published the paper. Shortly afterward, in 1962, NASA’s Mariner II spacecraft flew to Venus and encountered a constant stream of particles. This flow, called the solar wind, turned out to be incredibly influential on the workings of the solar system, including our lives on Earth.

Over his career, Parker also went on to study cosmic rays and the magnetic fields of galaxies, among many other related topics. His seminal ideas include the origin of magnetic fields, known as dynamo theory; rapid dissipation of magnetic fields; the structure of magnetized shock waves; and the diffusion of high-energy cosmic rays. His name is littered across astrophysics: the Parker instability, which describes magnetic fields in galaxies; the Parker equation, which describes particles moving through plasmas; the Sweet-Parker model of magnetic fields in plasmas; and the Parker limit on the flux of magnetic monopoles.

In 2017, NASA announced that it was naming its landmark solar mission after Parker as a recognition of his contributions to the field of heliophysics. On the morning of Aug. 12, 2018, Parker was at Cape Canaveral with three generations of his family to witness the launch of his namesake Parker Solar Probe, which has since completed multiple revolutions around the sun and collected extraordinary data.” [text selected from the obituary published in uchicago news]

Photo: Prof. Eugene N. Parker (1927-2022) [Credit: NASA RELEASE 22-025]

European Space Weather Week 2022 in Zagreb

European Space Weather Week (ESWW) is the main annual event in the European Space Weather calendar. It is an international meeting organised annually within the European Region in collaboration with prominent members of the European space weather community, such as European Space Agency (ESA). It began as a forum for the European Space Weather community and has since grown into an international event with global attendance.

This year ESWW will be co-organised by the Belgian Solar-Terrestrial Centre of Excellence and Hvar Observatory October 24-28, 2022 in Zagreb, Croatia. ESWW2022 will again adopt the central aim of bringing together the diverse groups in Europe working on different aspects of Space Weather and Space Climate: such as scientists, engineers, satellite operators, power grid technicians, communication and navigation specialists, people working in aviation, space weather service providers, STEM practitioners. The ESWW is highly interdisciplinary by nature and actively promotes investigation of new technologies and approaches. In addition, ESWW is an excellent place to meet people, to exchange knowledge and ideas, to discuss the latest on solar activity, how space weather influences the earth environment and our technologies, and how to deal with space weather. The overarching theme for ESWW2022 is ‘The importance of comprehensive space weather monitoring’, with a number of session topics, as well as the special ESWW2022 design reflecting this theme (the call-for-sessions and call-for-design are both currently open).

Figure: logo of the European Space Weather Week

Why is space weather so important: the SpaceX example

In the editorial paper “SpaceX—Sailing Close to the Space Weather?” of the new issue of Space Weather Journal the Editors remarked on the recent SpaceX satellite loss due to geomagnetic storm and lessons to be learned from the event.

“The 3 February 2022 launch of 49 of SpaceX’s Starlink satellites has provided a fascinating example of how even modest space weather can have significant practical and financial consequences. Enhanced atmospheric drag associated with a minor geomagnetic storm led to the loss of the majority of the 49 launched satellites. Although the 36th launch by SpaceX in the past 3 years, it was the first that experienced stormy space weather. We expect more stormy space weather as Solar Cycle 25 ramps up toward its peak expected in 2025. A subsequent Starlink launch on 21 February used a higher initial orbit at 300 km, reducing the payload from 49 to 46 satellites, and can be considered an agile response to the space weather losses experienced 2 weeks earlier. Lessons to be learned by the space industry and the space weather community are discussed, including a better dialog, nuanced understanding of space weather risks associated with modest events, but also an opportunity to investigate the space environment in relatively unexplored regions such as very low and high low Earth orbits.” [Hapgood et al., 2022]

Space weather is becoming a growing factor in our modern society, especially with private companies launching whole fleets of satellites into low Earth orbit. This recent SpaceX experience is a blatant example why space weather research and forecast are so important.

Figure: SpaceX Headquarters in December 2017; plumes from a flight of a Falcon 9 rocket are visible overhead [Credit: Wikimedia Commons, Iridium-4 Mission, 22 December 2017, 17:59, Official SpaceX Photos, donated to the public domain by SpaceX]